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

content/browser/android/content_readback_handler.cc

 // Copyright 2014 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 "content/browser/android/content_readback_handler.h"
 
 #include "base/android/jni_android.h"
 #include "base/bind.h"
+#include "cc/output/copy_output_request.h"
+#include "cc/output/copy_output_result.h"
 #include "content/browser/android/content_view_core_impl.h"
 #include "jni/ContentReadbackHandler_jni.h"
 #include "third_party/skia/include/core/SkBitmap.h"
+#include "ui/base/android/window_android.h"
+#include "ui/base/android/window_android_compositor.h"
 #include "ui/gfx/android/java_bitmap.h"
 #include "ui/gfx/rect.h"
 
 namespace content {
 
+namespace {
+
+typedef base::Callback<void(bool, const SkBitmap&)> ResultCallback;
+
+void OnFinishCopyOutputRequest(
+    const ResultCallback& result_callback,
+    scoped_ptr<cc::CopyOutputResult> copy_output_result) {
+  if (!copy_output_result->HasBitmap()) {
+    result_callback.Run(false, SkBitmap());
+    return;
+  }
+
+  scoped_ptr<SkBitmap> bitmap = copy_output_result->TakeBitmap();
+  result_callback.Run(true, *bitmap.Pass());
+}
+
+}  // anonymous namespace
+
 // static
 bool ContentReadbackHandler::RegisterContentReadbackHandler(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
 ContentReadbackHandler::ContentReadbackHandler(JNIEnv* env, jobject obj)
     : weak_factory_(this) {
   java_obj_.Reset(env, obj);
 }
 
-ContentReadbackHandler::~ContentReadbackHandler() {}
-
 void ContentReadbackHandler::Destroy(JNIEnv* env, jobject obj) {
   delete this;
 }
 
-void ContentReadbackHandler::OnFinishContentReadback(int readback_id,
-                                                     bool success,
-                                                     const SkBitmap& bitmap) {
-  JNIEnv* env = base::android::AttachCurrentThread();
-  ScopedJavaLocalRef<jobject> java_bitmap;
-  if (success)
-    java_bitmap = gfx::ConvertToJavaBitmap(&bitmap);
-
-  Java_ContentReadbackHandler_notifyGetContentBitmapFinished(
-      env, java_obj_.obj(), readback_id, success, java_bitmap.obj());
-}
-
 void ContentReadbackHandler::GetContentBitmap(JNIEnv* env,
                                               jobject obj,
                                               jint readback_id,
                                               jfloat scale,
                                               jobject config,
                                               jfloat x,
                                               jfloat y,
                                               jfloat width,
                                               jfloat height,
                                               jobject content_view_core) {
   ContentViewCore* view =
       ContentViewCore::GetNativeContentViewCore(env, content_view_core);
   DCHECK(view);
 
-  base::Callback<void(bool, const SkBitmap&)> result_callback =
-      base::Bind(&ContentReadbackHandler::OnFinishContentReadback,
+  ResultCallback result_callback =
+      base::Bind(&ContentReadbackHandler::OnFinishReadback,
                  weak_factory_.GetWeakPtr(),
                  readback_id);
 
   view->GetScaledContentBitmap(
       scale, config, gfx::Rect(x, y, width, height), result_callback);
-  return;
+}
+
+void ContentReadbackHandler::GetCompositorBitmap(JNIEnv* env,
+                                                 jobject obj,
+                                                 jint readback_id,
+                                                 jlong native_window_android) {
+  ui::WindowAndroid* window_android =
+      reinterpret_cast<ui::WindowAndroid*>(native_window_android);
+  DCHECK(window_android);
+
+  ResultCallback result_callback =
+      base::Bind(&ContentReadbackHandler::OnFinishReadback,
+                 weak_factory_.GetWeakPtr(),
+                 readback_id);
+
+  base::Callback<void(scoped_ptr<cc::CopyOutputResult>)> copy_output_callback =
+      base::Bind(&OnFinishCopyOutputRequest,
+                 result_callback);
+
+  ui::WindowAndroidCompositor* compositor = window_android->GetCompositor();
+
+  if (!compositor) {
+    copy_output_callback.Run(cc::CopyOutputResult::CreateEmptyResult());
+    return;
+  }
+
+  compositor->RequestCopyOfOutputOnRootLayer(
+      cc::CopyOutputRequest::CreateBitmapRequest(copy_output_callback));
+}
+
+ContentReadbackHandler::~ContentReadbackHandler() {}
+
+void ContentReadbackHandler::OnFinishReadback(int readback_id,
+                                              bool success,
+                                              const SkBitmap& bitmap) {
+  JNIEnv* env = base::android::AttachCurrentThread();
+  ScopedJavaLocalRef<jobject> java_bitmap;
+  if (success)
+    java_bitmap = gfx::ConvertToJavaBitmap(&bitmap);
+
+  Java_ContentReadbackHandler_notifyGetBitmapFinished(
+      env, java_obj_.obj(), readback_id, success, java_bitmap.obj());
 }
 
 // static
 static jlong Init(JNIEnv* env, jobject obj) {
   ContentReadbackHandler* content_readback_handler =
       new ContentReadbackHandler(env, obj);
   return reinterpret_cast<intptr_t>(content_readback_handler);
 }
 
 }  // namespace content