Revert of [android] Make RWHVAndroid a BeginFrameObserver.

ui/android/window_android.cc

Index: ui/android/window_android.cc
diff --git a/ui/android/window_android.cc b/ui/android/window_android.cc
index 79472befe6973cb2f905d9ef992650f92122fd6a..cff32ba6f571def1c787cd219296027d86f1cbc8 100644
--- a/ui/android/window_android.cc
+++ b/ui/android/window_android.cc
@@ -10,10 +10,6 @@
 #include "base/android/jni_string.h"
 #include "base/android/jni_weak_ref.h"
 #include "base/android/scoped_java_ref.h"
-#include "base/auto_reset.h"
-#include "base/observer_list.h"
-#include "cc/output/begin_frame_args.h"
-#include "cc/scheduler/begin_frame_source.h"
 #include "jni/WindowAndroid_jni.h"
 #include "ui/android/window_android_compositor.h"
 #include "ui/android/window_android_observer.h"
@@ -25,97 +21,8 @@
 using base::android::JavaRef;
 using base::android::ScopedJavaLocalRef;
 
-class WindowAndroid::WindowBeginFrameSource : public cc::BeginFrameSource {
- public:
-  explicit WindowBeginFrameSource(WindowAndroid* window)
-      : window_(window),
-        observer_count_(0),
-        in_on_vsync_(false) {}
-  ~WindowBeginFrameSource() override {}
-
-  // cc::BeginFrameSource implementation.
-  void AddObserver(cc::BeginFrameObserver* obs) override;
-  void RemoveObserver(cc::BeginFrameObserver* obs) override;
-  void DidFinishFrame(cc::BeginFrameObserver* obs,
-                      size_t remaining_frames) override {}
-  bool IsThrottled() const override { return true; }
-
-  void OnVSync(base::TimeTicks frame_time,
-               base::TimeDelta vsync_period);
-
- private:
-  WindowAndroid* const window_;
-  base::ObserverList<cc::BeginFrameObserver> observers_;
-  int observer_count_;
-  cc::BeginFrameArgs last_begin_frame_args_;
-  bool in_on_vsync_;
-};
-
-void WindowAndroid::WindowBeginFrameSource::AddObserver(
-    cc::BeginFrameObserver* obs) {
-  DCHECK(obs);
-  DCHECK(!observers_.HasObserver(obs));
-
-  observers_.AddObserver(obs);
-  observer_count_++;
-  obs->OnBeginFrameSourcePausedChanged(false);
-  window_->SetNeedsBeginFrames(true);
-
-  // Send a MISSED BeginFrame if possible and necessary. If an observer is added
-  // during OnVSync(), it will get a NORMAL BeginFrame from OnVSync() instead.
-  if (!in_on_vsync_ && last_begin_frame_args_.IsValid()) {
-    cc::BeginFrameArgs last_args = obs->LastUsedBeginFrameArgs();
-    if (!last_args.IsValid() ||
-        last_args.frame_time < last_begin_frame_args_.frame_time) {
-      last_begin_frame_args_.type = cc::BeginFrameArgs::MISSED;
-      // TODO(crbug.com/602485): A deadline doesn't make too much sense
-      // for a missed BeginFrame (the intention rather is 'immediately'),
-      // but currently the retro frame logic is very strict in discarding
-      // BeginFrames.
-      last_begin_frame_args_.deadline =
-          base::TimeTicks::Now() + last_begin_frame_args_.interval;
-      obs->OnBeginFrame(last_begin_frame_args_);
-    }
-  }
-}
-
-void WindowAndroid::WindowBeginFrameSource::RemoveObserver(
-    cc::BeginFrameObserver* obs) {
-  DCHECK(obs);
-  DCHECK(observers_.HasObserver(obs));
-
-  observers_.RemoveObserver(obs);
-  observer_count_--;
-  if (observer_count_ <= 0)
-    window_->SetNeedsBeginFrames(false);
-}
-
-void WindowAndroid::WindowBeginFrameSource::OnVSync(
-    base::TimeTicks frame_time,
-    base::TimeDelta vsync_period) {
-  // frame time is in the past, so give the next vsync period as the deadline.
-  base::TimeTicks deadline = frame_time + vsync_period;
-  last_begin_frame_args_ =
-      cc::BeginFrameArgs::Create(BEGINFRAME_FROM_HERE, frame_time, deadline,
-                                 vsync_period, cc::BeginFrameArgs::NORMAL);
-  DCHECK(last_begin_frame_args_.IsValid());
-
-  // We support adding/removing observers during observer iteration through
-  // base::ObserverList. We also prevent observers that are added during
-  // observer iteration from receiving a MISSED BeginFrame by means of
-  // |in_on_vsync_| - they will receive the current NORMAL one during the
-  // iteration instead. Note that SynchronousCompositorBrowserFilter relies on
-  // this behavior.
-  base::AutoReset<bool> auto_reset(&in_on_vsync_, true);
-  for (auto& obs : observers_)
-    obs.OnBeginFrame(last_begin_frame_args_);
-}
-
 WindowAndroid::WindowAndroid(JNIEnv* env, jobject obj, int display_id)
-    : display_id_(display_id),
-      compositor_(NULL),
-      begin_frame_source_(new WindowBeginFrameSource(this)),
-      needs_begin_frames_(false) {
+    : display_id_(display_id), compositor_(NULL) {
   java_window_.Reset(env, obj);
 }
 
@@ -162,10 +69,6 @@
   observer_list_.RemoveObserver(observer);
 }
 
-cc::BeginFrameSource* WindowAndroid::GetBeginFrameSource() {
-  return begin_frame_source_.get();
-}
-
 void WindowAndroid::AttachCompositor(WindowAndroidCompositor* compositor) {
   if (compositor_ && compositor != compositor_)
     DetachCompositor();
@@ -187,15 +90,6 @@
   Java_WindowAndroid_requestVSyncUpdate(env, GetJavaObject());
 }
 
-void WindowAndroid::SetNeedsBeginFrames(bool needs_begin_frames) {
-  if (needs_begin_frames_ == needs_begin_frames)
-    return;
-
-  needs_begin_frames_ = needs_begin_frames;
-  if (needs_begin_frames_)
-    RequestVSyncUpdate();
-}
-
 void WindowAndroid::SetNeedsAnimate() {
   if (compositor_)
     compositor_->SetNeedsAnimate();
@@ -213,9 +107,10 @@
   base::TimeTicks frame_time(base::TimeTicks::FromInternalValue(time_micros));
   base::TimeDelta vsync_period(
       base::TimeDelta::FromMicroseconds(period_micros));
-  begin_frame_source_->OnVSync(frame_time, vsync_period);
-  if (needs_begin_frames_)
-    RequestVSyncUpdate();
+  for (WindowAndroidObserver& observer : observer_list_)
+    observer.OnVSync(frame_time, vsync_period);
+  if (compositor_)
+    compositor_->OnVSync(frame_time, vsync_period);
 }
 
 void WindowAndroid::OnVisibilityChanged(JNIEnv* env,