Hide fullscreen rotation jank

content/browser/renderer_host/render_widget_host_view_android.h

Index: content/browser/renderer_host/render_widget_host_view_android.h
diff --git a/content/browser/renderer_host/render_widget_host_view_android.h b/content/browser/renderer_host/render_widget_host_view_android.h
index c5cf9d70df876c9abfbee6658f456b7abaafd833..ee69c278547a82e812a6c89740ba5f59e82be939 100644
--- a/content/browser/renderer_host/render_widget_host_view_android.h
+++ b/content/browser/renderer_host/render_widget_host_view_android.h
@@ -29,6 +29,7 @@
 #include "content/browser/renderer_host/text_input_manager.h"
 #include "content/common/content_export.h"
 #include "content/public/browser/readback_types.h"
+#include "content/public/browser/web_contents_observer.h"
 #include "gpu/command_buffer/common/mailbox.h"
 #include "third_party/skia/include/core/SkColor.h"
 #include "ui/android/delegated_frame_host_android.h"
@@ -70,6 +71,7 @@ class CONTENT_EXPORT RenderWidgetHostViewAndroid
       public ui::TouchSelectionControllerClient,
       public content::ContentViewCoreImplObserver,
       public content::TextInputManager::Observer,
+      public content::WebContentsObserver,

[Khushal, 2017/06/07 05:36:01]

You can not use WebContentsObserver here. renderer_host can not know about
web_contents.
https://cs.chromium.org/chromium/src/content/browser/renderer_host/DEPS.

I think plumbing it to the current RWHV from WebContentsImpl will be better.
Something like:
static_cast<RenderWidgetHostViewAndroid*>(GetRenderWidgetHostViewAndroid())->DidToggleFullscreenModeForTab.

[steimel, 2017/06/13 23:15:44]

Done.

       public ui::DelegatedFrameHostAndroid::Client,
       public cc::BeginFrameObserver {
  public:
@@ -204,6 +206,10 @@ class CONTENT_EXPORT RenderWidgetHostViewAndroid
   void OnAttachedToWindow() override;
   void OnDetachedFromWindow() override;
 
+  // content::WebContentsObserver implementation.
+  void DidToggleFullscreenModeForTab(bool entered_fullscreen,
+                                     bool will_cause_resize) override;
+
   // viz::FrameEvictor implementation
   void EvictDelegatedFrame() override;
 
@@ -236,6 +242,7 @@ class CONTENT_EXPORT RenderWidgetHostViewAndroid
   // Non-virtual methods
   void SetContentViewCore(ContentViewCoreImpl* content_view_core);
   SkColor GetCachedBackgroundColor() const;
+  bool can_use_static_layer() const { return !fullscreen_transitioning_; }
   void SendKeyEvent(const NativeWebKeyboardEvent& event);
   void SendMouseEvent(const ui::MotionEventAndroid&, int action_button);
   void SendMouseWheelEvent(const blink::WebMouseWheelEvent& event);
@@ -345,6 +352,10 @@ class CONTENT_EXPORT RenderWidgetHostViewAndroid
 
   void CreateOverscrollControllerIfPossible();
 
+  bool HasFullscreenTransitionJank(const cc::CompositorFrame& frame) const;

[mlamouri (slow - plz ping), 2017/06/12 13:10:07]

nit: that name is quite confusing as we don't know if there is a jank. Maybe
rename to something like "ShouldHideFullscreenTransition"?

[steimel, 2017/06/13 23:15:44]

Refactoring replaced all three of these functions with a single function
containing all the logic

+  void HideFullscreenTransitionJank();

[mlamouri (slow - plz ping), 2017/06/12 13:10:07]

nit: maybe drop "jank"?

[steimel, 2017/06/13 23:15:44]

Same as above

+  void EndFullscreenTransition();

[mlamouri (slow - plz ping), 2017/06/12 13:10:07]

Can we re-use this for non-fullscreen transitions? Like simple
portrait<->landscape transitions?

[steimel, 2017/06/13 23:15:44]

The new function should be re-useable

+
   // The model object.
   RenderWidgetHostImpl* host_;
 
@@ -424,6 +435,9 @@ class CONTENT_EXPORT RenderWidgetHostViewAndroid
   float prev_top_shown_pix_;
   float prev_bottom_shown_pix_;
 
+  bool fullscreen_transitioning_ = false;
+  bool awaiting_resize_ = false;
+
   cc::mojom::MojoCompositorFrameSinkClient* renderer_compositor_frame_sink_ =
       nullptr;