Enables compositing support for webview.

content/renderer/browser_plugin/browser_plugin_compositing_helper.cc

+// Copyright (c) 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 "content/renderer/browser_plugin/browser_plugin_compositing_helper.h"
+
+#include "cc/texture_layer.h"
+#include "content/common/browser_plugin_messages.h"
+#include "content/renderer/render_thread_impl.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebPluginContainer.h"
+#include "webkit/compositor_bindings/web_layer_impl.h"
+
+namespace content {
+
+static void SendACK(const std::string& mailbox_name,
+                    int host_route_id,
+                    int gpu_route_id,
+                    int gpu_host_id,
+                    unsigned sync_point) {
+  RenderThread::Get()->Send(
+      new BrowserPluginHostMsg_BuffersSwappedACK(
+          host_route_id,
+          gpu_route_id,
+          gpu_host_id,
+          mailbox_name,
+          sync_point));
+}
+
+BrowserPluginCompositingHelper::BrowserPluginCompositingHelper(
+    WebKit::WebPluginContainer* container,
+    int host_routing_id)
+    : host_routing_id_(host_routing_id),
+      last_mailbox_valid_(false),
+      container_(container) {
+}
+
+BrowserPluginCompositingHelper::~BrowserPluginCompositingHelper() {
+  container_->setWebLayer(NULL);
+}
+
+void BrowserPluginCompositingHelper::EnableCompositing(bool enable) {
+  if (enable && !texture_layer_) {
+      texture_layer_ = cc::TextureLayer::createForMailbox();

[rjkroege, 2013/01/10 17:03:21]

nit: wrong # of spaces at start of line? Chrome indents should be 2.

[alexst (slow to review), 2013/01/10 18:56:31]

Sigh, too much jumping between cc and content. Done

+      web_layer_.reset(new WebKit::WebLayerImpl(texture_layer_));
+  }
+
+  container_->setWebLayer(enable ? web_layer_.get() : NULL);
+}
+
+void BrowserPluginCompositingHelper::OnBuffersSwapped(const gfx::Size& size,
+                                               const std::string& mailbox_name,
+                                               int gpu_route_id,
+                                               int gpu_host_id) {
+  if (!last_mailbox_valid_)
+    SendACK(std::string(), host_routing_id_, gpu_route_id, gpu_host_id, 0);
+
+  last_mailbox_valid_ = !mailbox_name.empty();
+  texture_layer_->setTextureMailbox(mailbox_name,
+                                    base::Bind(&SendACK,
+                                               mailbox_name,
+                                               host_routing_id_,
+                                               gpu_route_id,
+                                               gpu_host_id));
+}
+
+}  // namespace content