[Android] Implement asynchronous zero-copy bitmap capture API.

content/public/browser/android/content_view_core.h

Index: content/public/browser/android/content_view_core.h
diff --git a/content/public/browser/android/content_view_core.h b/content/public/browser/android/content_view_core.h
index 8437e7bbd43c2240ae299aaf077937f55dab57ab..0f79e68ebd75aca43369c6e8bb1791c792ebde3a 100644
--- a/content/public/browser/android/content_view_core.h
+++ b/content/public/browser/android/content_view_core.h
@@ -11,8 +11,8 @@
 #include "base/callback.h"
 #include "content/common/content_export.h"
 #include "content/public/browser/navigation_controller.h"
-
-class SkBitmap;
+#include "third_party/skia/include/core/SkBitmap.h"
+#include "ui/gfx/rect.h"
 
 namespace cc {
 class Layer;
@@ -32,6 +32,10 @@ class WindowAndroid;
 namespace content {
 class WebContents;
 
+typedef base::Callback<void(SkBitmap*& bitmap,
+                            const gfx::Size&,
+                            SkBitmap::Config)> BitmapAllocator;
+
 // Native side of the ContentViewCore.java, which is the primary way of
 // communicating with the native Chromium code on Android.  This is a
 // public interface used by native code outside of the content module.
@@ -53,10 +57,17 @@ class CONTENT_EXPORT ContentViewCore {
   // Request a scaled content readback.  The result is passed through the
   // callback.  The boolean parameter indicates whether the readback was a
   // success or not.  The content is passed through the SkBitmap parameter.
-  // |out_size| is returned with the size of the content.
+  // |bitmap_config| is optional parameter to specify the configuration of the
+  // output bitmap.
+  // |bounding_rect| is optional parameter to specify the bounds of the capture.
+  // |bitmap_allocator| is optional parameter to specify custom bitmap allocator
+  // to be used while sending back the bitmap.
   virtual void GetScaledContentBitmap(
       float scale,
-      const base::Callback<void(bool, const SkBitmap&)>& result_callback) = 0;
+      const base::Callback<void(bool, const SkBitmap&)>& result_callback,
+      SkBitmap::Config bitmap_config = SkBitmap::kARGB_8888_Config,
+      const gfx::Rect& bounding_rect = gfx::Rect(),
+      const BitmapAllocator bitmap_allocator = BitmapAllocator()) = 0;
   virtual float GetDpiScale() const = 0;
   virtual void PauseVideo() = 0;
   virtual void PauseOrResumeGeolocation(bool should_pause) = 0;