Expand UMA coverage for compositor-handled events and fling FPS

content/child/blink_platform_impl.cc

 // 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 "content/child/blink_platform_impl.h"
 
 #include <math.h>
 
 #include <vector>
 
@@ skipping 1005 matching lines @@
 
 void BlinkPlatformImpl::callOnMainThread(
     void (*func)(void*), void* context) {
   main_thread_task_runner_->PostTask(FROM_HERE, base::Bind(func, context));
 }
 
 blink::WebGestureCurve* BlinkPlatformImpl::createFlingAnimationCurve(
     blink::WebGestureDevice device_source,
     const blink::WebFloatPoint& velocity,
     const blink::WebSize& cumulative_scroll) {
-  auto curve = WebGestureCurveImpl::CreateFromDefaultPlatformCurve(
-      gfx::Vector2dF(velocity.x, velocity.y),
-      gfx::Vector2dF(cumulative_scroll.width, cumulative_scroll.height));
-  return curve.release();
+  bool is_main_thread =
+      main_thread_task_runner_.get() &&
+      main_thread_task_runner_->BelongsToCurrentThread();
+  return WebGestureCurveImpl::CreateFromDefaultPlatformCurve(
+             gfx::Vector2dF(velocity.x, velocity.y),
+             gfx::Vector2dF(cumulative_scroll.width, cumulative_scroll.height),
+             is_main_thread).release();
 }
 
 void BlinkPlatformImpl::didStartWorkerRunLoop(
     const blink::WebWorkerRunLoop& runLoop) {
   WorkerTaskRunner* worker_task_runner = WorkerTaskRunner::Instance();
   worker_task_runner->OnWorkerRunLoopStarted(runLoop);
 }
 
 void BlinkPlatformImpl::didStopWorkerRunLoop(
     const blink::WebWorkerRunLoop& runLoop) {
@@ skipping 181 matching lines @@
 }
 
 // static
 void BlinkPlatformImpl::DestroyCurrentThread(void* thread) {
   WebThreadImplForMessageLoop* impl =
       static_cast<WebThreadImplForMessageLoop*>(thread);
   delete impl;
 }
 
 }  // namespace content