[gin] Add a v8::Platform implementation to allow for v8 posting tasks

This currently has no effect unless concurrent sweeping and job based
sweeping is turned on in v8.

BUG=v8:3015
R=abarth@chromium.org,dcarney@chromium.org

Review URL: https://codereview.chromium.org/225413004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@261872 0039d316-1c4b-4281-b951-d872f2087c98

build/common.gypi

@@ -1317,6 +1317,9 @@
     # Compile d8 for the host toolset.
     'v8_toolset_for_d8': 'host',
 
+    # Compiles v8 without its platform library.
+    'v8_use_default_platform': 0,
+
     # Use the chromium skia by default.
     'use_system_skia%': '0',
 

gin/gin.gyp

@@ -12,7 +12,9 @@
       'type': '<(component)',
       'dependencies': [
         '../base/base.gyp:base',
+        '../base/third_party/dynamic_annotations/dynamic_annotations.gyp:dynamic_annotations',
         '../v8/tools/gyp/v8.gyp:v8',
+
       ],
       'export_dependent_settings': [
         '../base/base.gyp:base',
@@ -58,13 +60,15 @@
         'public/context_holder.h',
         'public/gin_embedders.h',
         'public/isolate_holder.h',
+        'public/v8_platform.h',
         'public/wrapper_info.h',
         'runner.cc',
         'runner.h',
         'shell_runner.cc',
         'shell_runner.h',
         'try_catch.cc',
         'try_catch.h',
+        'v8_platform.cc',
         'wrappable.cc',
         'wrappable.h',
         'wrapper_info.cc',

gin/isolate_holder.cc

@@ -13,6 +13,7 @@
 #include "gin/array_buffer.h"
 #include "gin/function_template.h"
 #include "gin/per_isolate_data.h"
+#include "gin/public/v8_platform.h"
 
 namespace gin {
 
@@ -36,6 +37,7 @@ void EnsureV8Initialized(bool gin_managed) {
   if (!gin_managed)
     return;
 
+  v8::V8::InitializePlatform(V8Platform::Get());
   v8::V8::SetArrayBufferAllocator(ArrayBufferAllocator::SharedInstance());
   static const char v8_flags[] = "--use_strict --harmony";
   v8::V8::SetFlagsFromString(v8_flags, sizeof(v8_flags) - 1);

gin/per_isolate_data.cc

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 #include "base/logging.h"
+#include "base/message_loop/message_loop_proxy.h"
 #include "gin/per_isolate_data.h"
 #include "gin/public/gin_embedders.h"
 
@@ -18,7 +19,9 @@ namespace gin {
 
 PerIsolateData::PerIsolateData(Isolate* isolate,
                                ArrayBuffer::Allocator* allocator)
-    : isolate_(isolate), allocator_(allocator) {
+    : isolate_(isolate),
+      allocator_(allocator),
+      message_loop_proxy_(base::MessageLoopProxy::current()) {
   isolate_->SetData(kEmbedderNativeGin, this);
 }
 

gin/per_isolate_data.h

@@ -8,10 +8,15 @@
 #include <map>
 
 #include "base/basictypes.h"
+#include "base/memory/ref_counted.h"
 #include "gin/gin_export.h"
 #include "gin/public/wrapper_info.h"
 #include "v8/include/v8.h"
 
+namespace base {
+class MessageLoopProxy;
+}
+
 namespace gin {
 
 class IndexedPropertyInterceptor;
@@ -60,6 +65,9 @@ class GIN_EXPORT PerIsolateData {
 
   v8::Isolate* isolate() { return isolate_; }
   v8::ArrayBuffer::Allocator* allocator() { return allocator_; }
+  base::MessageLoopProxy* message_loop_proxy() {
+    return message_loop_proxy_.get();
+  }
 
  private:
   typedef std::map<
@@ -79,6 +87,7 @@ class GIN_EXPORT PerIsolateData {
   FunctionTemplateMap function_templates_;
   IndexedPropertyInterceptorMap indexed_interceptors_;
   NamedPropertyInterceptorMap named_interceptors_;
+  scoped_refptr<base::MessageLoopProxy> message_loop_proxy_;
 
   DISALLOW_COPY_AND_ASSIGN(PerIsolateData);
 };

gin/public/v8_platform.h

@@ -0,0 +1,38 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef GIN_PUBLIC_V8_PLATFORM_H_
+#define GIN_PUBLIC_V8_PLATFORM_H_
+
+#include "base/basictypes.h"
+#include "base/compiler_specific.h"
+#include "base/lazy_instance.h"
+#include "gin/gin_export.h"
+#include "v8/include/v8-platform.h"
+
+namespace gin {
+
+// A v8::Platform implementation to use with gin.
+class GIN_EXPORT V8Platform : public NON_EXPORTED_BASE(v8::Platform) {
+ public:
+  static V8Platform* Get();
+
+  // v8::Platform implementation.
+  virtual void CallOnBackgroundThread(
+      v8::Task* task,
+      v8::Platform::ExpectedRuntime expected_runtime) OVERRIDE;
+  virtual void CallOnForegroundThread(v8::Isolate* isolate,
+                                      v8::Task* task) OVERRIDE;
+ private:
+  friend struct base::DefaultLazyInstanceTraits<V8Platform>;
+
+  V8Platform();
+  virtual ~V8Platform();
+
+  DISALLOW_COPY_AND_ASSIGN(V8Platform);
+};
+
+}  // namespace gin
+
+#endif  // GIN_PUBLIC_V8_PLATFORM_H_

gin/v8_platform.cc

@@ -0,0 +1,42 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "gin/public/v8_platform.h"
+
+#include "base/bind.h"
+#include "base/location.h"
+#include "base/message_loop/message_loop_proxy.h"
+#include "base/threading/worker_pool.h"
+#include "gin/per_isolate_data.h"
+
+namespace gin {
+
+namespace {
+
+base::LazyInstance<V8Platform>::Leaky g_v8_platform = LAZY_INSTANCE_INITIALIZER;
+
+}  // namespace
+
+// static
+V8Platform* V8Platform::Get() { return g_v8_platform.Pointer(); }
+
+V8Platform::V8Platform() {}
+
+V8Platform::~V8Platform() {}
+
+void V8Platform::CallOnBackgroundThread(
+    v8::Task* task,
+    v8::Platform::ExpectedRuntime expected_runtime) {
+  base::WorkerPool::PostTask(
+      FROM_HERE,
+      base::Bind(&v8::Task::Run, base::Owned(task)),
+      expected_runtime == v8::Platform::kLongRunningTask);
+}
+
+void V8Platform::CallOnForegroundThread(v8::Isolate* isolate, v8::Task* task) {
+  PerIsolateData::From(isolate)->message_loop_proxy()->PostTask(
+      FROM_HERE, base::Bind(&v8::Task::Run, base::Owned(task)));
+}
+
+}  // namespace gin