Implement frame attribution (FrameBlamer)

components/scheduler/renderer/renderer_scheduler.h

Index: components/scheduler/renderer/renderer_scheduler.h
diff --git a/components/scheduler/renderer/renderer_scheduler.h b/components/scheduler/renderer/renderer_scheduler.h
index 98635ba6be4efc692a9f5239c6d485204eff9608..58c982e7781cb98cb9778e2f4f9af5aae3391da0 100644
--- a/components/scheduler/renderer/renderer_scheduler.h
+++ b/components/scheduler/renderer/renderer_scheduler.h
@@ -13,11 +13,18 @@
 #include "components/scheduler/scheduler_export.h"
 #include "third_party/WebKit/public/web/WebInputEvent.h"
 
+namespace base {
+namespace trace_event {
+class BlameContext;
+}
+}
+
 namespace cc {
 struct BeginFrameArgs;
 }
 
 namespace blink {
+class WebLocalFrame;
 class WebThread;
 }
 
@@ -151,6 +158,11 @@ class SCHEDULER_EXPORT RendererScheduler : public ChildScheduler {
   // received via OnRendererBackgrounded. Defaults to disabled.
   virtual void SetTimerQueueSuspensionWhenBackgroundedEnabled(bool enabled) = 0;
 
+  // Sets the default blame context to which top level work should be
+  // attributed in this renderer. |blame_context| must outlive this scheduler.
+  virtual void SetTopLevelBlameContext(
+      base::trace_event::BlameContext* blame_context) = 0;
+
  protected:
   RendererScheduler();
   DISALLOW_COPY_AND_ASSIGN(RendererScheduler);