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 220 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 can_show_thumbnail_placeholder() const {

[Khushal, 2017/06/14 19:43:14]

nit: not a trivial accessor. CanShowThumbnailPlaceholder and define in .cc?

[steimel, 2017/06/14 21:46:16]

Done.

+    return !(fullscreen_state_ == FullscreenState::kEnteringFullscreen ||
+             fullscreen_state_ == FullscreenState::kExitingFullscreen ||
+             fullscreen_state_ == FullscreenState::kFullscreenRotation);
+  }
   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;
   }
   void set_selection_popup_controller(SelectionPopupController* controller) {
     selection_popup_controller_ = controller;
   }
 
   base::WeakPtr<RenderWidgetHostViewAndroid> GetWeakPtrAndroid();
 
   bool OnTouchEvent(const ui::MotionEvent& event);
   bool OnTouchHandleEvent(const ui::MotionEvent& event);
   int GetTouchHandleHeight();
   void ResetGestureDetection();
   void SetDoubleTapSupportEnabled(bool enabled);
   void SetMultiTouchZoomSupportEnabled(bool enabled);
 
   void WasResized();
 
+  void OnFullscreenStateChanged(bool entered_fullscreen);
+
   bool HasValidFrame() const;
 
   void MoveCaret(const gfx::Point& point);
   void ShowContextMenuAtPoint(const gfx::Point& point, ui::MenuSourceType);
   void DismissTextHandles();
   void SetTextHandlesTemporarilyHidden(bool hidden);
   void OnShowUnhandledTapUIIfNeeded(int x_dip, int y_dip);
   void OnSelectWordAroundCaretAck(bool did_select,
                                   int start_adjust,
                                   int end_adjust);
@@ skipping 66 matching lines @@
   void RequestDisallowInterceptTouchEvent();
 
   bool SyncCompositorOnMessageReceived(const IPC::Message& message);
 
   void ComputeEventLatencyOSTouchHistograms(const ui::MotionEvent& event);
 
   void CreateOverscrollControllerIfPossible();
 
   WebContentsAccessibilityAndroid* GetWebContentsAccessibilityAndroid() const;
 
+  void EvictFrameIfNecessary(bool physical_backing_resized);
+  enum class FullscreenState {

[Khushal, 2017/06/14 19:43:14]

nit: Generally this would be at the beginning of the private declarations.

[steimel, 2017/06/14 21:46:16]

Done.

+    kNotFullscreen,
+    kEnteringFullscreen,
+    kFullscreen,
+    kExitingFullscreen,
+    kFullscreenRotation,
+  };
+
   // 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;
+  bool awaiting_resize_ = false;

[Khushal, 2017/06/14 19:43:14]

nit: fullscreen_transition_awaiting_resize_?

And could you add a comment documenting the use? There are 2 things to note:

1) We are assuming that every transition to/from fullscreen will be followed by
a change in view's physical backing size (which is basically the android Surface
size).

2) And while we could simply take a mismatch in fullscreen states as the trigger
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. Which is why we defer assuming the
transition to be completed until a resize event is received.

[steimel, 2017/06/14 21:46:16]

Done.

+  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_