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

content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java

Index: content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java
diff --git a/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java b/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java
index 83a974da9d8d20ca33eab34d38b9dbe2914e9888..f1a017f12b25f68f6778a79f4f621e57a51d1448 100644
--- a/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java
+++ b/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java
@@ -1063,6 +1063,16 @@ public class ContentViewCore
         return null;
     }
 
+    public void getBitmapAsync(int x, int y, int width, int height,
+        float scale, Bitmap.Config bitmapConfig) {
+        if (mNativeContentViewCore == 0 || width == 0 || height == 0
+                || getViewportWidthPix() == 0 || getViewportHeightPix() == 0) {
+            return;
+        }
+        nativePopulateBitmapFromCompositorAsync(mNativeContentViewCore,
+            x, y, width, height, scale, bitmapConfig);
+    }
+
     /**
      * Generates a bitmap of the content that is performance optimized based on capture time.
      *
@@ -1233,6 +1243,12 @@ public class ContentViewCore
 
     @SuppressWarnings("unused")
     @CalledByNative
+    private void onBitmapReady(boolean result, Bitmap bitmap) {
+
+    }
+
+    @SuppressWarnings("unused")
+    @CalledByNative
     private void onFlingStartEventConsumed(int vx, int vy) {
         temporarilyHideTextHandles();
         for (mGestureStateListenersIterator.rewind();
@@ -3446,6 +3462,9 @@ public class ContentViewCore
     private native boolean nativePopulateBitmapFromCompositor(long nativeContentViewCoreImpl,
             Bitmap bitmap);
 
+    private native void nativePopulateBitmapFromCompositorAsync(long nativeContentViewCoreImpl,
+            int x, int y, int width, int height, float scale, Bitmap.Config bitmapConfig);
+
     private native void nativeWasResized(long nativeContentViewCoreImpl);
 
     private native boolean nativeIsRenderWidgetHostViewReady(long nativeContentViewCoreImpl);