Defer render_widget draw until host window is available

content/renderer/render_view_impl.cc

 // Copyright (c) 2012 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/render_view_impl.h"
 
 #include <algorithm>
 #include <cmath>
 #include <string>
 #include <vector>
@@ skipping 390 matching lines @@
       last_page_id_sent_to_browser_(-1),
       next_page_id_(next_page_id),
       history_list_offset_(-1),
       history_list_length_(0),
       target_url_status_(TARGET_NONE),
       selection_text_offset_(0),
       cached_is_main_frame_pinned_to_left_(false),
       cached_is_main_frame_pinned_to_right_(false),
       cached_has_main_frame_horizontal_scrollbar_(false),
       cached_has_main_frame_vertical_scrollbar_(false),
+      context_has_swapbuffers_complete_callback_(false),
+      queried_for_swapbuffers_complete_callback_(false),
       ALLOW_THIS_IN_INITIALIZER_LIST(cookie_jar_(this)),
       geolocation_dispatcher_(NULL),
       speech_input_dispatcher_(NULL),
       device_orientation_dispatcher_(NULL),
       media_stream_dispatcher_(NULL),
       p2p_socket_dispatcher_(NULL),
       devtools_agent_(NULL),
       renderer_accessibility_(NULL),
       mouse_lock_dispatcher_(NULL),
       session_storage_namespace_id_(session_storage_namespace_id),
@@ skipping 4092 matching lines @@
        plugin_it != plugin_delegates_.end(); ++plugin_it) {
     (*plugin_it)->SetContainerVisibility(true);
   }
 #endif  // OS_MACOSX
 }
 
 bool RenderViewImpl::SupportsAsynchronousSwapBuffers() {
   if (WebWidgetHandlesCompositorScheduling())
     return false;
 
+  if (queried_for_swapbuffers_complete_callback_)
+    return context_has_swapbuffers_complete_callback_;
+
+  queried_for_swapbuffers_complete_callback_ = true;
+
   WebKit::WebGraphicsContext3D* context = webview()->graphicsContext3D();
-  if (!context)
-    return false;
-  if (!context->makeContextCurrent())
-    return false;
-  std::string extensions(context->getRequestableExtensionsCHROMIUM().utf8());
-  return extensions.find("GL_CHROMIUM_swapbuffers_complete_callback") !=
-      std::string::npos;
+  if (context && context->makeContextCurrent()) {
+    std::string extensions(context->getRequestableExtensionsCHROMIUM().utf8());
+    context_has_swapbuffers_complete_callback_ =
+        extensions.find("GL_CHROMIUM_swapbuffers_complete_callback")
+            != std::string::npos;
+  }
+
+  return context_has_swapbuffers_complete_callback_;
 }
 
 void RenderViewImpl::OnSetFocus(bool enable) {
   RenderWidget::OnSetFocus(enable);
 
   if (webview() && webview()->isActive()) {
     // Notify all NPAPI plugins.
     std::set<WebPluginDelegateProxy*>::iterator plugin_it;
     for (plugin_it = plugin_delegates_.begin();
          plugin_it != plugin_delegates_.end(); ++plugin_it) {
@@ skipping 434 matching lines @@
 bool RenderViewImpl::WebWidgetHandlesCompositorScheduling() const {
   return !!RenderThreadImpl::current()->compositor_thread();
 }
 
 void RenderViewImpl::OnJavaBridgeInit() {
   DCHECK(!java_bridge_dispatcher_.get());
 #if defined(ENABLE_JAVA_BRIDGE)
   java_bridge_dispatcher_.reset(new JavaBridgeDispatcher(this));
 #endif
 }