LockCompositingSurface to make sure frame is not evicted.

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 55 matching lines @@
 // See comments in render_widget_host_view.h about this class and its members.
 // -----------------------------------------------------------------------------
 class CONTENT_EXPORT RenderWidgetHostViewAndroid
     : public RenderWidgetHostViewBase,
       public cc::SurfaceFactoryClient,
       public ui::GestureProviderClient,
       public ui::WindowAndroidObserver,
       public DelegatedFrameEvictorClient,
       public StylusTextSelectorClient,
       public ui::TouchSelectionControllerClient,
-      public content::ContentViewCoreImplObserver {
+      public content::ContentViewCoreImplObserver,
+      public base::SupportsWeakPtr<RenderWidgetHostViewAndroid> {

[no sievers, 2016/06/01 22:32:06]

There is already a |weak_ptr_factory_| in this class that you can use.

[sivag, 2016/06/02 14:34:50]

Done.

  public:
   RenderWidgetHostViewAndroid(RenderWidgetHostImpl* widget,
                               ContentViewCoreImpl* content_view_core);
   ~RenderWidgetHostViewAndroid() override;
 
   void Blur();
 
   // RenderWidgetHostView implementation.
   bool OnMessageReceived(const IPC::Message& msg) override;
   void InitAsChild(gfx::NativeView parent_view) override;
@@ skipping 190 matching lines @@
   void ShowInternal();
   void HideInternal();
   void AttachLayers();
   void RemoveLayers();
 
   void UpdateBackgroundColor(SkColor color);
 
   // Called after async screenshot task completes. Scales and crops the result
   // of the copy.
   static void PrepareTextureCopyOutputResult(
+      base::WeakPtr<RenderWidgetHostViewAndroid> rwhva,
       const gfx::Size& dst_size_in_pixel,
       SkColorType color_type,
       const base::TimeTicks& start_time,
       const ReadbackRequestCallback& callback,
       std::unique_ptr<cc::CopyOutputResult> result);
 
   // DevTools ScreenCast support for Android WebView.
   void SynchronousCopyContents(const gfx::Rect& src_subrect_in_pixel,
                                const gfx::Size& dst_size_in_pixel,
                                const ReadbackRequestCallback& callback,
@@ skipping 109 matching lines @@
   gfx::Vector2dF last_scroll_offset_;
 
   base::WeakPtrFactory<RenderWidgetHostViewAndroid> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewAndroid);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_ANDROID_H_