android: add Java-side support for browser compositor async readback

ui/base/android/window_android.cc

 // Copyright 2013 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.
 
 #include "ui/base/android/window_android.h"
 
 #include "base/android/jni_android.h"
 #include "base/android/jni_array.h"
 #include "base/android/jni_weak_ref.h"
 #include "base/android/scoped_java_ref.h"
@@ skipping 23 matching lines @@
 bool WindowAndroid::RegisterWindowAndroid(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
 WindowAndroid::~WindowAndroid() {
   DCHECK(!compositor_);
   FOR_EACH_OBSERVER(
       WindowAndroidObserver, observer_list_, OnWillDestroyWindow());
 }
 
-bool WindowAndroid::GrabSnapshot(
-    int content_x, int content_y, int width, int height,
-    std::vector<unsigned char>* png_representation) {
-  JNIEnv* env = AttachCurrentThread();
-  ScopedJavaLocalRef<jbyteArray> result =
-      Java_WindowAndroid_grabSnapshot(env, GetJavaObject().obj(),
-                                      content_x + content_offset_.x(),
-                                      content_y + content_offset_.y(),
-                                      width, height);
-  if (result.is_null())
-    return false;
-  base::android::JavaByteArrayToByteVector(
-      env, result.obj(), png_representation);
-  return true;
-}
-
 void WindowAndroid::OnCompositingDidCommit() {
   FOR_EACH_OBSERVER(WindowAndroidObserver,
                     observer_list_,
                     OnCompositingDidCommit());
 }
 
 void WindowAndroid::AddObserver(WindowAndroidObserver* observer) {
   if (!observer_list_.HasObserver(observer))
     observer_list_.AddObserver(observer);
 }
@@ skipping 38 matching lines @@
 // ----------------------------------------------------------------------------
 // Native JNI methods
 // ----------------------------------------------------------------------------
 
 jlong Init(JNIEnv* env, jobject obj, jlong vsync_period) {
   WindowAndroid* window = new WindowAndroid(env, obj, vsync_period);
   return reinterpret_cast<intptr_t>(window);
 }
 
 }  // namespace ui