Send idle notifications to V8 after commit

content/renderer/gpu/render_widget_compositor.cc

Index: content/renderer/gpu/render_widget_compositor.cc
diff --git a/content/renderer/gpu/render_widget_compositor.cc b/content/renderer/gpu/render_widget_compositor.cc
index d21b85bcc42af66ba2ba9fe3263bac6ca0ce3aad..d653d2e7d5a2c932ac2662bd26b00967173df121 100644
--- a/content/renderer/gpu/render_widget_compositor.cc
+++ b/content/renderer/gpu/render_widget_compositor.cc
@@ -38,6 +38,7 @@
 #include "third_party/WebKit/public/platform/WebCompositeAndReadbackAsyncCallback.h"
 #include "third_party/WebKit/public/platform/WebSelectionBound.h"
 #include "third_party/WebKit/public/platform/WebSize.h"
+#include "third_party/WebKit/public/web/WebKit.h"
 #include "third_party/WebKit/public/web/WebWidget.h"
 #include "ui/gfx/frame_time.h"
 #include "ui/gl/gl_switches.h"
@@ -173,6 +174,8 @@ scoped_ptr<RenderWidgetCompositor> RenderWidgetCompositor::Create(
       !cmd->HasSwitch(switches::kDisableGpuVsync);
   settings.begin_frame_scheduling_enabled =
       cmd->HasSwitch(switches::kEnableBeginFrameScheduling);
+  settings.send_v8_idle_notification_after_commit =

[jamesr, 2014/08/18 23:23:49]

you're setting this here in content/renderer/...

+      cmd->HasSwitch(cc::switches::kSendV8IdleNotificationAfterCommit);
   settings.main_frame_before_activation_enabled =
       cmd->HasSwitch(cc::switches::kEnableMainFrameBeforeActivation) &&
       !cmd->HasSwitch(cc::switches::kDisableMainFrameBeforeActivation);
@@ -757,6 +760,7 @@ void RenderWidgetCompositor::DidBeginMainFrame() {
 }
 
 void RenderWidgetCompositor::BeginMainFrame(const cc::BeginFrameArgs& args) {
+  begin_main_frame_args_ = args;
   double frame_time = (args.frame_time - base::TimeTicks()).InSecondsF();
   WebBeginFrameArgs web_begin_frame_args = WebBeginFrameArgs(frame_time);
   widget_->webwidget()->beginFrame(web_begin_frame_args);
@@ -785,6 +789,14 @@ void RenderWidgetCompositor::WillCommit() {
 }
 
 void RenderWidgetCompositor::DidCommit() {
+  int idle_time_for_gc =
+      std::max(0L, (begin_main_frame_args_.frame_time +
+                    begin_main_frame_args_.interval -
+                    base::TimeTicks::HighResNow()).InMilliseconds());
+  if (layer_tree_host_->settings().send_v8_idle_notification_after_commit &&

[jamesr, 2014/08/18 23:23:49]

... and then querying it again here, in the same object. there's no need to
involve the cc:: settings object at all. just store a bool or query the flag
status again here

[ernstm, 2014/08/18 23:46:34]

Done.

+      idle_time_for_gc)
+    blink::mainThreadIsolate()->IdleNotification(idle_time_for_gc);
+
   widget_->DidCommitCompositorFrame();
   widget_->didBecomeReadyForAdditionalInput();
 }