Add switch to configure gpu memory limit

Bug: 923141
Test: None
Change-Id: I0c53c2272eda161a1d2d6ac16b66f260bd72dfd1
Reviewed-on: https://chromium-review.googlesource.com/c/1431133
Commit-Queue: Mitsuru Oshima <oshima@chromium.org>
Reviewed-by: Antoine Labour <piman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#625542}

ui/compositor/compositor.cc

@@ -179,6 +179,20 @@ Compositor::Compositor(
 #endif
 
   settings.memory_policy.bytes_limit_when_visible = 512 * 1024 * 1024;
+
+  // Used to configure ui compositor memory limit for chromeos devices.
+  // See crbug.com/923141.
+  if (command_line->HasSwitch(
+          switches::kUiCompositorMemoryLimitWhenVisibleMB)) {
+    std::string value_str = command_line->GetSwitchValueASCII(
+        switches::kUiCompositorMemoryLimitWhenVisibleMB);
+    unsigned value_in_mb;
+    if (base::StringToUint(value_str, &value_in_mb)) {
+      settings.memory_policy.bytes_limit_when_visible =
+          1024 * 1024 * value_in_mb;
+    }
+  }
+
   settings.memory_policy.priority_cutoff_when_visible =
       gpu::MemoryAllocation::CUTOFF_ALLOW_NICE_TO_HAVE;
 

ui/compositor/compositor_switches.cc

@@ -29,6 +29,9 @@ const char kUISlowAnimations[] = "ui-slow-animations";
 
 const char kDisableVsyncForTests[] = "disable-vsync-for-tests";
 
+const char kUiCompositorMemoryLimitWhenVisibleMB[] =
+    "ui-compositor-memory-limit-when-visible-mb";
+
 }  // namespace switches
 
 namespace features {

ui/compositor/compositor_switches.h

@@ -18,6 +18,7 @@ COMPOSITOR_EXPORT extern const char kUIDisableZeroCopy[];
 COMPOSITOR_EXPORT extern const char kUIShowPaintRects[];
 COMPOSITOR_EXPORT extern const char kUISlowAnimations[];
 COMPOSITOR_EXPORT extern const char kDisableVsyncForTests[];
+COMPOSITOR_EXPORT extern const char kUiCompositorMemoryLimitWhenVisibleMB[];
 
 }  // namespace switches