Disable partial swaps for webview guest renderer until we can figure out how to do that properly.

content/renderer/render_widget.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_widget.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
@@ skipping 121 matching lines @@
       surface_id_(0),
       webwidget_(NULL),
       opener_id_(MSG_ROUTING_NONE),
       init_complete_(false),
       current_paint_buf_(NULL),
       next_paint_flags_(0),
       filtered_time_per_frame_(0.0f),
       update_reply_pending_(false),
       need_update_rect_for_auto_resize_(false),
       using_asynchronous_swapbuffers_(false),
+      allow_partial_swap_(true),
       num_swapbuffers_complete_pending_(0),
       did_show_(false),
       is_hidden_(false),
       is_fullscreen_(false),
       needs_repainting_on_restore_(false),
       has_focus_(false),
       handling_input_event_(false),
       handling_ime_event_(false),
       closing_(false),
       is_swapped_out_(swapped_out),
@@ skipping 1189 matching lines @@
   // DoDeferredUpdate() is bypassed and WebKit is responsible for exiting and
   // entering force compositing mode at the appropriate times.
   if (!is_threaded_compositing_enabled_)
     webwidget_->enterForceCompositingMode(false);
 }
 
 void RenderWidget::initializeLayerTreeView(
     WebKit::WebLayerTreeViewClient* client,
     const WebKit::WebLayer& root_layer,
     const WebKit::WebLayerTreeView::Settings& settings) {
-  compositor_ = RenderWidgetCompositor::Create(this, client, settings);
+  WebKit::WebLayerTreeView::Settings override_settings = settings;
+  override_settings.partialSwapEnabled = allow_partial_swap_;

[jamesr, 2013/03/06 19:30:28]

Yuck yuck yuck!  RenderWidgetCompositor has a RenderWidget*, can't it just ask
the RenderWidget questions like this directly instead of bouncing through a
WebKit struct?

[alexst (slow to review), 2013/03/06 20:34:07]

This seemed like a related field in the struct, I didn't realize dependency on
it was undesirable. I'll re-plumb. 

+  compositor_ = RenderWidgetCompositor::Create(this,
+                                               client,
+                                               override_settings);
   if (!compositor_)
     return;
 
   compositor_->setRootLayer(root_layer);
   compositor_->setViewportSize(size_, physical_backing_size_);
   if (init_complete_)
     compositor_->setSurfaceReady();
 }
 
 WebKit::WebLayerTreeView* RenderWidget::layerTreeView() {
@@ skipping 793 matching lines @@
 bool RenderWidget::WillHandleGestureEvent(
     const WebKit::WebGestureEvent& event) {
   return false;
 }
 
 bool RenderWidget::HasTouchEventHandlersAt(const gfx::Point& point) const {
   return true;
 }
 
 }  // namespace content