Hide fullscreen rotation jank

content/browser/renderer_host/render_widget_host_view_android.h

 // Copyright (c) 2012 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 CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_ANDROID_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_ANDROID_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 143 matching lines @@
   void ClearCompositorFrame() override;
   void SetIsInVR(bool is_in_vr) override;
   bool IsInVR() const override;
   void DidOverscroll(const ui::DidOverscrollParams& params) override;
   void DidStopFlinging() override;
   void ShowDisambiguationPopup(const gfx::Rect& rect_pixels,
                                const SkBitmap& zoomed_bitmap) override;
   std::unique_ptr<SyntheticGestureTarget> CreateSyntheticGestureTarget()
       override;
   void OnDidNavigateMainFrameToNewPage() override;
+  void OnFullscreenStateChanged(bool entered_fullscreen) override;
   void SetNeedsBeginFrames(bool needs_begin_frames) override;
   cc::FrameSinkId GetFrameSinkId() override;
   cc::FrameSinkId FrameSinkIdAtPoint(cc::SurfaceHittestDelegate* delegate,
                                      const gfx::Point& point,
                                      gfx::Point* transformed_point) override;
   void ProcessMouseEvent(const blink::WebMouseEvent& event,
                          const ui::LatencyInfo& latency) override;
   void ProcessMouseWheelEvent(const blink::WebMouseWheelEvent& event,
                               const ui::LatencyInfo& latency) override;
   void ProcessTouchEvent(const blink::WebTouchEvent& event,
@@ skipping 57 matching lines @@
   void ReclaimResources(const cc::ReturnedResourceArray& resources) override;
 
   // cc::BeginFrameObserver implementation.
   void OnBeginFrame(const cc::BeginFrameArgs& args) override;
   const cc::BeginFrameArgs& LastUsedBeginFrameArgs() const override;
   void OnBeginFrameSourcePausedChanged(bool paused) override;
 
   // Non-virtual methods
   void SetContentViewCore(ContentViewCoreImpl* content_view_core);
   SkColor GetCachedBackgroundColor() const;
+  bool CanShowThumbnailPlaceholder() const;
   void SendKeyEvent(const NativeWebKeyboardEvent& event);
   void SendMouseEvent(const ui::MotionEventAndroid&, int action_button);
   void SendMouseWheelEvent(const blink::WebMouseWheelEvent& event);
   void SendGestureEvent(const blink::WebGestureEvent& event);
   void ResolveTapDisambiguation(double timestamp_seconds,
                                 gfx::Point tap_viewport_offset,
                                 bool is_long_press);
   void set_ime_adapter(ImeAdapterAndroid* ime_adapter) {
     ime_adapter_android_ = ime_adapter;
   }
@@ skipping 46 matching lines @@
                               RenderWidgetHostViewBase* updated_view) override;
   void OnTextSelectionChanged(TextInputManager* text_input_manager,
                               RenderWidgetHostViewBase* updated_view) override;
 
   ImeAdapterAndroid* ime_adapter_for_testing() { return ime_adapter_android_; }
 
   // Exposed for tests.
   cc::SurfaceId SurfaceIdForTesting() const override;
 
  private:
+  enum class FullscreenState {
+    kNotFullscreen,
+    kEnteringFullscreen,
+    kFullscreen,
+    kExitingFullscreen,
+    kFullscreenRotation,
+  };
+
   void RunAckCallbacks();
 
   void SendReclaimCompositorResources(bool is_swap_ack);
 
   void OnFrameMetadataUpdated(const cc::CompositorFrameMetadata& frame_metadata,
                               bool is_transparent);
 
   void ShowInternal();
   void HideInternal();
   void AttachLayers();
@@ skipping 25 matching lines @@
   void RequestDisallowInterceptTouchEvent();
 
   bool SyncCompositorOnMessageReceived(const IPC::Message& message);
 
   void ComputeEventLatencyOSTouchHistograms(const ui::MotionEvent& event);
 
   void CreateOverscrollControllerIfPossible();
 
   WebContentsAccessibilityAndroid* GetWebContentsAccessibilityAndroid() const;
 
+  void UpdateFullscreenState(bool physical_backing_resized);
+
   // The model object.
   RenderWidgetHostImpl* host_;
 
   // The begin frame source being observed.  Null if none.
   cc::BeginFrameSource* begin_frame_source_;
   cc::BeginFrameArgs last_begin_frame_args_;
   uint32_t latest_confirmed_begin_frame_source_id_;
   uint64_t latest_confirmed_begin_frame_sequence_number_;
 
   // Indicates whether and for what reason a request for begin frames has been
@@ skipping 59 matching lines @@
   std::unique_ptr<viz::FrameEvictor> frame_evictor_;
 
   bool observing_root_window_;
 
   // The last scroll offset of the view.
   gfx::Vector2dF last_scroll_offset_;
 
   float prev_top_shown_pix_;
   float prev_bottom_shown_pix_;
 
+  FullscreenState fullscreen_state_ = FullscreenState::kNotFullscreen;
+
+  // While we could simply take a mismatch in fullscreen states as the trigger

[aelias_OOO_until_Jul13, 2017/06/16 22:46:41]

I think there's a bug on the renderer side then.  CC is misreporting a frame as
being fullscreen in its metadata, when its size is still the old non-fullscreen
size.  Please find a way to defer the fullscreen metadata setting in the
renderer instead of working around the problem here.

[Khushal, 2017/06/19 18:46:34]

We use the state transitions in FullscreenController.h to set the fullscreen
state for a frame coming from the renderer. Are we doing something incorrect
there?

If the state reported in the CompositorFrame is correct then the scenario where
I expect waiting for a resize to help is the case where the renderer transitions
to fullscreen and sends a frame with the previous size before the android
Surface is resized.

[aelias_OOO_until_Jul13, 2017/06/19 19:01:32]

I'm not sure precisely what is going wrong, but it seems wrong in principle for
CC to report a frame with the non-fullscreen size as being fullscreen.  Instead
of waiting on the browser side for the size to change, I suggest something on
the renderer should be waiting for the size to change before flipping
is_fullscreen.

Or, what I would find even nicer is for is_fullscreen not be introduced at all,
for example if you use another signal like the transparency status of the
surface, or if you find a better way to obtain the expected final size on the
browser and then wait for all sizes to converge to it.

+  // for a transition, and assume the transition to have finished once the
+  // fullscreen states and sizes match, we have cases where we reach this
+  // consistent state before the physical backing size changes. Therefore we
+  // defer assuming the transition to be completed until a resize event is
+  // received, which is marked by |fullscreen_transition_awaiting_resize_|.
+  //
+  // Note that this assumes that every transition will be followed by a change
+  // in the view's physical backing size.
+  bool fullscreen_transition_awaiting_resize_ = false;
+  bool current_frame_is_fullscreen_ = false;
+  bool web_contents_is_fullscreen_ = false;
+
   cc::mojom::MojoCompositorFrameSinkClient* renderer_compositor_frame_sink_ =
       nullptr;
 
   base::ObserverList<DestructionObserver> destruction_observers_;
 
   MouseWheelPhaseHandler mouse_wheel_phase_handler_;
 
   base::WeakPtrFactory<RenderWidgetHostViewAndroid> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewAndroid);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_ANDROID_H_