cc: Implement deadine scheduling disabled by default

content/browser/renderer_host/render_widget_host_view_aura.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/browser/renderer_host/render_widget_host_view_aura.h"
 
 #include "base/basictypes.h"
 #include "base/bind.h"
 #include "base/callback_helpers.h"
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
 #include "base/message_loop/message_loop.h"
 #include "base/strings/string_number_conversions.h"
 #include "cc/output/compositor_frame.h"
 #include "cc/output/compositor_frame_ack.h"
 #include "cc/output/copy_output_request.h"
 #include "cc/output/copy_output_result.h"
 #include "cc/resources/texture_mailbox.h"
+#include "cc/trees/layer_tree_settings.h"
 #include "content/browser/accessibility/browser_accessibility_manager.h"
 #include "content/browser/accessibility/browser_accessibility_state_impl.h"
 #include "content/browser/aura/compositor_resize_lock.h"
 #include "content/browser/renderer_host/backing_store_aura.h"
 #include "content/browser/renderer_host/dip_util.h"
 #include "content/browser/renderer_host/overscroll_controller.h"
 #include "content/browser/renderer_host/render_view_host_delegate.h"
 #include "content/browser/renderer_host/render_widget_host_impl.h"
 #include "content/browser/renderer_host/touch_smooth_scroll_gesture_aura.h"
 #include "content/browser/renderer_host/ui_events_helper.h"
@@ skipping 2943 matching lines @@
   // should display a renderer frame.
   if (!compositor->IsLocked() && can_lock_compositor_ == YES_DID_LOCK) {
     can_lock_compositor_ = NO_PENDING_RENDERER_FRAME;
   }
 }
 
 void RenderWidgetHostViewAura::OnUpdateVSyncParameters(
     ui::Compositor* compositor,
     base::TimeTicks timebase,
     base::TimeDelta interval) {
-  if (IsShowing() && !last_draw_ended_.is_null())
-    host_->UpdateVSyncParameters(last_draw_ended_, interval);
+  if (IsShowing()) {
+    if (compositor->layer_tree_settings().deadline_scheduling_enabled) {
+      // The deadline scheduler has logic to stagger the draws of the
+      // Renderer and Browser built-in, so send it an accurate timebase.
+      host_->UpdateVSyncParameters(timebase, interval);
+    } else if (!last_draw_ended_.is_null()) {
+      // For the non-deadline scheduler, we send the Renderer an offset
+      // vsync timebase to avoid its draws racing the Browser's draws.
+      host_->UpdateVSyncParameters(last_draw_ended_, interval);
+    }
+  }
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // RenderWidgetHostViewAura, BrowserAccessibilityDelegate implementation:
 
 void RenderWidgetHostViewAura::SetAccessibilityFocus(int acc_obj_id) {
   if (!host_)
     return;
 
   host_->AccessibilitySetFocus(acc_obj_id);
@@ skipping 292 matching lines @@
     RenderWidgetHost* widget) {
   return new RenderWidgetHostViewAura(widget);
 }
 
 // static
 void RenderWidgetHostViewPort::GetDefaultScreenInfo(WebScreenInfo* results) {
   GetScreenInfoForWindow(results, NULL);
 }
 
 }  // namespace content