Move WebGL blacklist decision making to GPU process.

Still, if we pass in a commandline switch to disable WebGL1/2, they are still pass to renderer process as WebPreferences. BUG=744658 TEST=bots R=kbr@chromium.org,piman@chromium.org Cq-Include-Trybots: master.tryserver.chromium.android:android_optional_gpu_tests_rel;master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel Change-Id: I15fc34bc72d1c86d31d392bd34230d366564c318 Reviewed-on: https://chromium-review.googlesource.com/659100 Commit-Queue: Zhenyao Mo <zmo@chromium.org> Reviewed-by: Daniel Cheng <dcheng@chromium.org> Reviewed-by: Bill Budge <bbudge@chromium.org> Reviewed-by: Bo <boliu@chromium.org> Reviewed-by: Kenneth Russell <kbr@chromium.org> Reviewed-by: Antoine Labour <piman@chromium.org> Cr-Commit-Position: refs/heads/master@{#502466}
Denger-Network · Sep 16, 2017 · a3fda99 · a3fda99
1 parent d15c799
commit a3fda99
Show file tree

Hide file tree

Showing 86 changed files with 198 additions and 232 deletions.
diff --git a/android_webview/browser/aw_settings.cc b/android_webview/browser/aw_settings.cc
@@ -434,9 +434,10 @@ void AwSettings::PopulateWebPreferencesLocked(JNIEnv* env,
     // Using 100M instead of max int to avoid overflows.
     web_prefs->minimum_accelerated_2d_canvas_size = 100 * 1000 * 1000;
   }
-  web_prefs->experimental_webgl_enabled =
-      web_prefs->experimental_webgl_enabled &&
-      enable_supported_hardware_accelerated_features;
+  web_prefs->webgl1_enabled = web_prefs->webgl1_enabled &&
+                              enable_supported_hardware_accelerated_features;
+  web_prefs->webgl2_enabled = web_prefs->webgl2_enabled &&
+                              enable_supported_hardware_accelerated_features;
 
   // If strict mixed content checking is enabled then running should not be
   // allowed.

diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
@@ -420,12 +420,6 @@ const FeatureEntry::Choice kEnableGpuRasterizationChoices[] = {
      switches::kForceGpuRasterization, ""},
 };
 
-const FeatureEntry::Choice kEnableWebGL2Choices[] = {
-    {flags_ui::kGenericExperimentChoiceDefault, "", ""},
-    {flags_ui::kGenericExperimentChoiceEnabled, switches::kEnableES3APIs, ""},
-    {flags_ui::kGenericExperimentChoiceDisabled, switches::kDisableES3APIs, ""},
-};
-
 #if defined(OS_CHROMEOS)
 const FeatureEntry::Choice kMemoryPressureThresholdChoices[] = {
     {flags_ui::kGenericExperimentChoiceDefault, "", ""},
@@ -2445,9 +2439,6 @@ const FeatureEntry kFeatureEntries[] = {
      flag_descriptions::kAutomaticTabDiscardingDescription, kOsWin | kOsMac,
      FEATURE_VALUE_TYPE(features::kAutomaticTabDiscarding)},
 #endif  // OS_WIN || OS_MACOSX
-    {"enable-es3-apis", flag_descriptions::kWebgl2Name,
-     flag_descriptions::kWebgl2Description, kOsAll,
-     MULTI_VALUE_TYPE(kEnableWebGL2Choices)},
     {"enable-webfonts-intervention-v2",
      flag_descriptions::kEnableWebfontsInterventionName,
      flag_descriptions::kEnableWebfontsInterventionDescription, kOsAll,

diff --git a/chrome/browser/chrome_content_browser_client.cc b/chrome/browser/chrome_content_browser_client.cc
@@ -2448,8 +2448,10 @@ void ChromeContentBrowserClient::OverrideWebkitPrefs(
   web_prefs->loads_images_automatically =
       prefs->GetBoolean(prefs::kWebKitLoadsImagesAutomatically);
 
-  if (prefs->GetBoolean(prefs::kDisable3DAPIs))
-    web_prefs->experimental_webgl_enabled = false;
+  if (prefs->GetBoolean(prefs::kDisable3DAPIs)) {
+    web_prefs->webgl1_enabled = false;
+    web_prefs->webgl2_enabled = false;
+  }
 
   web_prefs->allow_running_insecure_content =
       prefs->GetBoolean(prefs::kWebKitAllowRunningInsecureContent);

diff --git a/chrome/browser/flag_descriptions.cc b/chrome/browser/flag_descriptions.cc
@@ -1430,9 +1430,6 @@ const char kWalletServiceUseSandboxName[] =
 const char kWalletServiceUseSandboxDescription[] =
     "For developers: use the sandbox service for Google Payments API calls.";
 
-const char kWebgl2Name[] = "WebGL 2.0";
-const char kWebgl2Description[] = "Allow web applications to access WebGL 2.0.";
-
 const char kWebglDraftExtensionsName[] = "WebGL Draft Extensions";
 const char kWebglDraftExtensionsDescription[] =
     "Enabling this option allows web applications to access the WebGL "

diff --git a/chrome/browser/flag_descriptions.h b/chrome/browser/flag_descriptions.h
@@ -881,9 +881,6 @@ extern const char kVideoRotateToFullscreenDescription[];
 extern const char kWalletServiceUseSandboxName[];
 extern const char kWalletServiceUseSandboxDescription[];
 
-extern const char kWebgl2Name[];
-extern const char kWebgl2Description[];
-
 extern const char kWebglDraftExtensionsName[];
 extern const char kWebglDraftExtensionsDescription[];
 

diff --git a/content/browser/gpu/compositor_util.cc b/content/browser/gpu/compositor_util.cc
@@ -80,7 +80,7 @@ const GpuFeatureInfo GetGpuFeatureInfo(size_t index, bool* eof) {
      " and hardware acceleration will be unavailable.",
      true},
     {kWebGLFeatureName, !manager->IsWebGLEnabled(),
-     command_line.HasSwitch(switches::kDisableExperimentalWebGL),
+     command_line.HasSwitch(switches::kDisableWebGL),
      "WebGL has been disabled via blacklist or the command line.", false},
     {"flash_3d", manager->IsFeatureBlacklisted(gpu::GPU_FEATURE_TYPE_FLASH3D),
      command_line.HasSwitch(switches::kDisableFlash3d),
@@ -142,7 +142,8 @@ const GpuFeatureInfo GetGpuFeatureInfo(size_t index, bool* eof) {
      " or command line.",
      true},
     {kWebGL2FeatureName, !manager->IsWebGL2Enabled(),
-     command_line.HasSwitch(switches::kDisableES3APIs),
+     command_line.HasSwitch(switches::kDisableWebGL) ||
+         command_line.HasSwitch(switches::kDisableWebGL2),
      "WebGL2 has been disabled via blacklist or the command line.", false},
     {kCheckerImagingFeatureName, false, !IsCheckerImagingEnabled(),
      "Checker-imaging has been disabled via finch trial or the command line.",

diff --git a/content/browser/gpu/gpu_data_manager_impl_private.cc b/content/browser/gpu/gpu_data_manager_impl_private.cc
@@ -126,6 +126,9 @@ int GetGpuBlacklistHistogramValueWin(gpu::GpuFeatureStatus status) {
     case gpu::kGpuFeatureStatusDisabled:
       entry_index += 2;
       break;
+    case gpu::kGpuFeatureStatusSoftware:
+      entry_index += 3;
+      break;
     case gpu::kGpuFeatureStatusUndefined:
     case gpu::kGpuFeatureStatusMax:
       NOTREACHED();
@@ -184,9 +187,9 @@ void UpdateStats(const gpu::GPUInfo& gpu_info,
       command_line.HasSwitch(switches::kDisableAccelerated2dCanvas),
       command_line.HasSwitch(switches::kDisableGpu),
       command_line.HasSwitch(switches::kDisableGpuRasterization),
-      command_line.HasSwitch(switches::kDisableExperimentalWebGL),
-      (!command_line.HasSwitch(switches::kEnableES3APIs) ||
-       command_line.HasSwitch(switches::kDisableES3APIs))};
+      command_line.HasSwitch(switches::kDisableWebGL),
+      (command_line.HasSwitch(switches::kDisableWebGL) ||
+       command_line.HasSwitch(switches::kDisableWebGL2))};
 #if defined(OS_WIN)
   const std::string kGpuBlacklistFeatureHistogramNamesWin[] = {
       "GPU.BlacklistFeatureTestResultsWindows.Accelerated2dCanvas",
@@ -813,7 +816,6 @@ void GpuDataManagerImplPrivate::UpdateRendererWebPrefs(
   DCHECK(prefs);
 
   if (!IsWebGLEnabled()) {
-    prefs->experimental_webgl_enabled = false;
     prefs->pepper_3d_enabled = false;
   }
   if (IsFeatureBlacklisted(gpu::GPU_FEATURE_TYPE_FLASH3D))
@@ -855,11 +857,6 @@ void GpuDataManagerImplPrivate::UpdateGpuPreferences(
   if (ShouldDisableAcceleratedVideoDecode(command_line))
     gpu_preferences->disable_accelerated_video_decode = true;
 
-  gpu_preferences->enable_es3_apis =
-      (command_line->HasSwitch(switches::kEnableES3APIs) ||
-       IsWebGL2Enabled()) &&
-      !command_line->HasSwitch(switches::kDisableES3APIs);
-
   gpu_preferences->gpu_program_cache_size =
       gpu::ShaderDiskCache::CacheSizeBytes();
 }

diff --git a/content/browser/renderer_host/render_process_host_impl.cc b/content/browser/renderer_host/render_process_host_impl.cc
@@ -2487,7 +2487,6 @@ void RenderProcessHostImpl::PropagateBrowserCommandLineToRenderer(
     switches::kDefaultTileWidth,
     switches::kDefaultTileHeight,
     switches::kDisable2dCanvasImageChromium,
-    switches::kDisable3DAPIs,
     switches::kDisableAcceleratedJpegDecoding,
     switches::kDisableAcceleratedVideoDecode,
     switches::kDisableBackgroundTimerThrottling,

diff --git a/content/browser/renderer_host/render_view_host_impl.cc b/content/browser/renderer_host/render_view_host_impl.cc
@@ -394,10 +394,11 @@ WebPreferences RenderViewHostImpl::ComputeWebkitPrefs() {
   prefs.databases_enabled =
       !command_line.HasSwitch(switches::kDisableDatabases);
 
-  prefs.experimental_webgl_enabled =
-      GpuProcessHost::gpu_enabled() &&
-      !command_line.HasSwitch(switches::kDisable3DAPIs) &&
-      !command_line.HasSwitch(switches::kDisableExperimentalWebGL);
+  prefs.webgl1_enabled = !command_line.HasSwitch(switches::kDisable3DAPIs) &&
+                         !command_line.HasSwitch(switches::kDisableWebGL);
+  prefs.webgl2_enabled = !command_line.HasSwitch(switches::kDisable3DAPIs) &&
+                         !command_line.HasSwitch(switches::kDisableWebGL) &&
+                         !command_line.HasSwitch(switches::kDisableWebGL2);
 
   prefs.pepper_3d_enabled =
       !command_line.HasSwitch(switches::kDisablePepper3d);

diff --git a/content/public/common/common_param_traits_macros.h b/content/public/common/common_param_traits_macros.h
@@ -156,7 +156,8 @@ IPC_STRUCT_TRAITS_BEGIN(content::WebPreferences)
   IPC_STRUCT_TRAITS_MEMBER(hyperlink_auditing_enabled)
   IPC_STRUCT_TRAITS_MEMBER(allow_universal_access_from_file_urls)
   IPC_STRUCT_TRAITS_MEMBER(allow_file_access_from_file_urls)
-  IPC_STRUCT_TRAITS_MEMBER(experimental_webgl_enabled)
+  IPC_STRUCT_TRAITS_MEMBER(webgl1_enabled)
+  IPC_STRUCT_TRAITS_MEMBER(webgl2_enabled)
   IPC_STRUCT_TRAITS_MEMBER(pepper_3d_enabled)
   IPC_STRUCT_TRAITS_MEMBER(record_whole_document)
   IPC_STRUCT_TRAITS_MEMBER(use_solid_color_scrollbars)

diff --git a/content/public/common/content_switches.cc b/content/public/common/content_switches.cc
@@ -125,8 +125,11 @@ const char kDisableDatabases[]              = "disable-databases";
 const char kDisableDomainBlockingFor3DAPIs[] =
     "disable-domain-blocking-for-3d-apis";
 
-// Disable experimental WebGL support.
-const char kDisableExperimentalWebGL[]      = "disable-webgl";
+// Disable all versions of WebGL.
+const char kDisableWebGL[] = "disable-webgl";
+
+// Disable WebGL2.
+const char kDisableWebGL2[] = "disable-webgl2";
 
 // Comma-separated list of feature names to disable. See also kEnableFeatures.
 const char kDisableFeatures[]               = "disable-features";

diff --git a/content/public/common/content_switches.h b/content/public/common/content_switches.h
@@ -48,7 +48,8 @@ CONTENT_EXPORT extern const char kDisableDatabases[];
 CONTENT_EXPORT extern const char kDisableDistanceFieldText[];
 CONTENT_EXPORT extern const char kDisableDisplayList2dCanvas[];
 extern const char kDisableDomainBlockingFor3DAPIs[];
-CONTENT_EXPORT extern const char kDisableExperimentalWebGL[];
+CONTENT_EXPORT extern const char kDisableWebGL[];
+CONTENT_EXPORT extern const char kDisableWebGL2[];
 CONTENT_EXPORT extern const char kDisableFeatures[];
 CONTENT_EXPORT extern const char kDisableFileSystem[];
 CONTENT_EXPORT extern const char kDisableFlash3d[];

diff --git a/content/public/common/web_preferences.cc b/content/public/common/web_preferences.cc
@@ -98,7 +98,8 @@ WebPreferences::WebPreferences()
       hyperlink_auditing_enabled(true),
       allow_universal_access_from_file_urls(false),
       allow_file_access_from_file_urls(false),
-      experimental_webgl_enabled(false),
+      webgl1_enabled(true),
+      webgl2_enabled(true),
       pepper_3d_enabled(false),
       flash_3d_enabled(true),
       flash_stage3d_enabled(false),

diff --git a/content/public/common/web_preferences.h b/content/public/common/web_preferences.h
@@ -129,7 +129,8 @@ struct CONTENT_EXPORT WebPreferences {
   bool hyperlink_auditing_enabled;
   bool allow_universal_access_from_file_urls;
   bool allow_file_access_from_file_urls;
-  bool experimental_webgl_enabled;
+  bool webgl1_enabled;
+  bool webgl2_enabled;
   bool pepper_3d_enabled;
   bool flash_3d_enabled;
   bool flash_stage3d_enabled;

diff --git a/content/renderer/pepper/pepper_plugin_instance_impl.cc b/content/renderer/pepper/pepper_plugin_instance_impl.cc
@@ -856,11 +856,6 @@ bool PepperPluginInstanceImpl::Initialize(
   UpdateTouchEventRequest();
   UpdateWheelEventRequest();
 
-  SetGPUHistogram(ppapi::Preferences(PpapiPreferencesBuilder::Build(
-                      render_frame_->render_view()->webkit_preferences())),
-                  arg_names,
-                  arg_values);
-
   argn_ = arg_names;
   argv_ = arg_values;
   std::unique_ptr<const char* []> argn_array(StringVectorToArgArray(argn_));

diff --git a/content/renderer/pepper/pepper_plugin_instance_metrics.cc b/content/renderer/pepper/pepper_plugin_instance_metrics.cc
@@ -73,30 +73,4 @@ void RecordFlashClickSizeMetric(int width, int height) {
                              height);
 }
 
-void SetGPUHistogram(const ppapi::Preferences& prefs,
-                     const std::vector<std::string>& arg_names,
-                     const std::vector<std::string>& arg_values) {
-// Calculate a histogram to let us determine how likely people are to try to
-// run Stage3D content on machines that have it blacklisted.
-#if defined(OS_WIN)
-  bool needs_gpu = false;
-
-  for (size_t i = 0; i < arg_names.size(); i++) {
-    if (arg_names[i] == "wmode") {
-      // In theory content other than Flash could have a "wmode" argument,
-      // but that's pretty unlikely.
-      if (arg_values[i] == "direct" || arg_values[i] == "gpu")
-        needs_gpu = true;
-      break;
-    }
-  }
-  // 0 : No 3D content and GPU is blacklisted
-  // 1 : No 3D content and GPU is not blacklisted
-  // 2 : 3D content but GPU is blacklisted
-  // 3 : 3D content and GPU is not blacklisted
-  UMA_HISTOGRAM_ENUMERATION("Flash.UsesGPU",
-                            needs_gpu * 2 + prefs.is_webgl_supported, 8);
-#endif
-}
-
 }  // namespace content
diff --git a/content/renderer/pepper/pepper_plugin_instance_metrics.h b/content/renderer/pepper/pepper_plugin_instance_metrics.h
@@ -5,13 +5,6 @@
 #ifndef CONTENT_RENDERER_PEPPER_PEPPER_PLUGIN_INSTANCE_METRICS_H_
 #define CONTENT_RENDERER_PEPPER_PEPPER_PLUGIN_INSTANCE_METRICS_H_
 
-#include <string>
-#include <vector>
-
-namespace ppapi {
-struct Preferences;
-}
-
 namespace content {
 
 // Record size metrics for all Flash instances.
@@ -20,10 +13,6 @@ void RecordFlashSizeMetric(int width, int height);
 // Records size metrics for Flash instances that are clicked.
 void RecordFlashClickSizeMetric(int width, int height);
 
-void SetGPUHistogram(const ppapi::Preferences& prefs,
-                     const std::vector<std::string>& arg_names,
-                     const std::vector<std::string>& arg_values);
-
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_PEPPER_PEPPER_PLUGIN_INSTANCE_METRICS_H_
diff --git a/content/renderer/pepper/ppapi_preferences_builder.cc b/content/renderer/pepper/ppapi_preferences_builder.cc
@@ -23,7 +23,6 @@ ppapi::Preferences PpapiPreferencesBuilder::Build(
   ppapi_prefs.is_stage3d_supported = prefs.flash_stage3d_enabled;
   ppapi_prefs.is_stage3d_baseline_supported =
       prefs.flash_stage3d_baseline_enabled;
-  ppapi_prefs.is_webgl_supported = prefs.experimental_webgl_enabled;
   ppapi_prefs.is_accelerated_video_decode_enabled =
       prefs.pepper_accelerated_video_decode_enabled;
   return ppapi_prefs;

diff --git a/content/renderer/render_frame_impl.cc b/content/renderer/render_frame_impl.cc
@@ -4741,15 +4741,12 @@ blink::WebString RenderFrameImpl::DoNotTrackValue() {
   return WebString();
 }
 
-bool RenderFrameImpl::AllowWebGL(bool default_value) {
-  if (!default_value)
-    return false;
-
+bool RenderFrameImpl::ShouldBlockWebGL() {
   bool blocked = true;
   Send(new FrameHostMsg_Are3DAPIsBlocked(
       routing_id_, url::Origin(frame_->Top()->GetSecurityOrigin()).GetURL(),
       THREE_D_API_TYPE_WEBGL, &blocked));
-  return !blocked;
+  return blocked;
 }
 
 bool RenderFrameImpl::AllowContentInitiatedDataUrlNavigations(

diff --git a/content/renderer/render_frame_impl.h b/content/renderer/render_frame_impl.h
@@ -661,7 +661,7 @@ class CONTENT_EXPORT RenderFrameImpl
   blink::WebEncryptedMediaClient* EncryptedMediaClient() override;
   blink::WebString UserAgentOverride() override;
   blink::WebString DoNotTrackValue() override;
-  bool AllowWebGL(bool default_value) override;
+  bool ShouldBlockWebGL() override;
   bool AllowContentInitiatedDataUrlNavigations(
       const blink::WebURL& url) override;
   blink::WebScreenOrientationClient* GetWebScreenOrientationClient() override;

diff --git a/content/renderer/render_view_impl.cc b/content/renderer/render_view_impl.cc
@@ -802,9 +802,8 @@ void RenderView::ApplyWebPreferences(const WebPreferences& prefs,
   settings->SetAllowFileAccessFromFileURLs(
       prefs.allow_file_access_from_file_urls);
 
-  // Enable experimental WebGL support if requested on command line
-  // and support is compiled in.
-  settings->SetExperimentalWebGLEnabled(prefs.experimental_webgl_enabled);
+  settings->SetWebGL1Enabled(prefs.webgl1_enabled);
+  settings->SetWebGL2Enabled(prefs.webgl2_enabled);
 
   // Enable WebGL errors to the JS console if requested.
   settings->SetWebGLErrorsToConsoleEnabled(

diff --git a/content/shell/renderer/layout_test/blink_test_helpers.cc b/content/shell/renderer/layout_test/blink_test_helpers.cc
@@ -32,7 +32,6 @@ void ExportLayoutTestSpecificPreferences(
   to->loads_images_automatically = from.loads_images_automatically;
   to->plugins_enabled = from.plugins_enabled;
   to->tabs_to_links = from.tabs_to_links;
-  to->experimental_webgl_enabled = from.experimental_webgl_enabled;
   // experimentalCSSRegionsEnabled is deprecated and ignored.
   to->hyperlink_auditing_enabled = from.hyperlink_auditing_enabled;
   to->allow_running_insecure_content = from.allow_running_of_insecure_content;

diff --git a/content/shell/test_runner/test_preferences.cc b/content/shell/test_runner/test_preferences.cc
@@ -22,7 +22,6 @@ void TestPreferences::Reset() {
   allow_file_access_from_file_urls = true;
   allow_running_of_insecure_content = true;
   default_text_encoding_name = WebString::FromUTF8("ISO-8859-1");
-  experimental_webgl_enabled = false;
   experimental_css_grid_layout_enabled = true;
   java_script_can_access_clipboard = true;
   supports_multiple_windows = true;

diff --git a/content/shell/test_runner/test_preferences.h b/content/shell/test_runner/test_preferences.h
@@ -19,7 +19,6 @@ struct TEST_RUNNER_EXPORT TestPreferences {
   bool allow_file_access_from_file_urls;
   bool allow_running_of_insecure_content;
   blink::WebString default_text_encoding_name;
-  bool experimental_webgl_enabled;
   bool experimental_css_grid_layout_enabled;
   bool java_script_can_access_clipboard;
   bool supports_multiple_windows;

diff --git a/content/shell/test_runner/test_runner.cc b/content/shell/test_runner/test_runner.cc
@@ -2416,8 +2416,6 @@ void TestRunner::OverridePreference(const std::string& key,
     prefs->plugins_enabled = value->BooleanValue();
   } else if (key == "WebKitTabToLinksPreferenceKey") {
     prefs->tabs_to_links = value->BooleanValue();
-  } else if (key == "WebKitWebGLEnabled") {
-    prefs->experimental_webgl_enabled = value->BooleanValue();
   } else if (key == "WebKitCSSGridLayoutEnabled") {
     prefs->experimental_css_grid_layout_enabled = value->BooleanValue();
   } else if (key == "WebKitHyperlinkAuditingEnabled") {

diff --git a/gpu/command_buffer/service/context_group.cc b/gpu/command_buffer/service/context_group.cc
@@ -128,12 +128,24 @@ ContextGroup::ContextGroup(
 bool ContextGroup::Initialize(GLES2Decoder* decoder,
                               ContextType context_type,
                               const DisallowedFeatures& disallowed_features) {
-  bool enable_es3 = context_type == CONTEXT_TYPE_OPENGLES3 ||
-                    context_type == CONTEXT_TYPE_WEBGL2;
-  if (!gpu_preferences_.enable_es3_apis && enable_es3) {
-    DLOG(ERROR) << "ContextGroup::Initialize failed because ES3 APIs are "
-                << "not available.";
-    return false;
+  switch (context_type) {
+    case CONTEXT_TYPE_WEBGL1:
+      if (kGpuFeatureStatusBlacklisted ==
+          gpu_feature_info_.status_values[GPU_FEATURE_TYPE_ACCELERATED_WEBGL]) {
+        DLOG(ERROR) << "ContextGroup::Initialize failed: WebGL1 baclklisted";
+        return false;
+      }
+      break;
+    case CONTEXT_TYPE_WEBGL2:
+      if (kGpuFeatureStatusBlacklisted ==
+          gpu_feature_info_
+              .status_values[GPU_FEATURE_TYPE_ACCELERATED_WEBGL2]) {
+        DLOG(ERROR) << "ContextGroup::Initialize failed: WebGL2 blacklisted";
+        return false;
+      }
+      break;
+    default:
+      break;
   }
   if (HaveContexts()) {
     if (context_type != feature_info_->context_type()) {
@@ -176,7 +188,9 @@ bool ContextGroup::Initialize(GLES2Decoder* decoder,
     }
   }
 
-  if (enable_es3 || feature_info_->feature_flags().ext_draw_buffers) {
+  if (context_type == CONTEXT_TYPE_OPENGLES3 ||
+      context_type == CONTEXT_TYPE_WEBGL2 ||
+      feature_info_->feature_flags().ext_draw_buffers) {
     GetIntegerv(GL_MAX_COLOR_ATTACHMENTS_EXT, &max_color_attachments_);
     if (max_color_attachments_ < 1)
       max_color_attachments_ = 1;