cc: Implement deadine scheduling disabled by default

cc/output/output_surface.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 "cc/output/output_surface.h"
 
+#include <algorithm>
 #include <set>
 #include <string>
 #include <vector>
 
 #include "base/bind.h"
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
 #include "base/message_loop/message_loop.h"
 #include "base/strings/string_split.h"
 #include "base/strings/string_util.h"
@@ skipping 137 matching lines @@
     skipped_begin_frame_args_ = args;
   } else {
     begin_frame_pending_ = true;
     client_->BeginFrame(args);
     // args might be an alias for skipped_begin_frame_args_.
     // Do not reset it before calling BeginFrame!
     skipped_begin_frame_args_ = BeginFrameArgs();
   }
 }
 
-base::TimeDelta OutputSurface::AlternateRetroactiveBeginFramePeriod() {
-  return BeginFrameArgs::DefaultRetroactiveBeginFramePeriod();
+base::TimeTicks OutputSurface::RetroactiveBeginFrameDeadline() {
+  // TODO(brianderson): Remove the alternative deadline once we have better
+  // deadline estimations.
+  base::TimeTicks alternative_deadline =
+      skipped_begin_frame_args_.frame_time +
+      BeginFrameArgs::DefaultRetroactiveBeginFramePeriod();
+  return std::max(skipped_begin_frame_args_.deadline, alternative_deadline);
 }
 
 void OutputSurface::PostCheckForRetroactiveBeginFrame() {
   if (!skipped_begin_frame_args_.IsValid() ||
       check_for_retroactive_begin_frame_pending_)
     return;
 
   base::MessageLoop::current()->PostTask(
      FROM_HERE,
      base::Bind(&OutputSurface::CheckForRetroactiveBeginFrame,
                 weak_ptr_factory_.GetWeakPtr()));
   check_for_retroactive_begin_frame_pending_ = true;
 }
 
 void OutputSurface::CheckForRetroactiveBeginFrame() {
   TRACE_EVENT0("cc", "OutputSurface::CheckForRetroactiveBeginFrame");
   check_for_retroactive_begin_frame_pending_ = false;
-  base::TimeTicks now = base::TimeTicks::Now();
-  // TODO(brianderson): Remove the alternative deadline once we have better
-  // deadline estimations.
-  base::TimeTicks alternative_deadline =
-      skipped_begin_frame_args_.frame_time +
-      AlternateRetroactiveBeginFramePeriod();
-  if (now < skipped_begin_frame_args_.deadline ||
-      now < alternative_deadline) {
+  if (base::TimeTicks::Now() < RetroactiveBeginFrameDeadline())
     BeginFrame(skipped_begin_frame_args_);
-  }
 }
 
 void OutputSurface::DidSwapBuffers() {
   begin_frame_pending_ = false;
   pending_swap_buffers_++;
   TRACE_EVENT1("cc", "OutputSurface::DidSwapBuffers",
                "pending_swap_buffers_", pending_swap_buffers_);
   if (frame_rate_controller_)
     frame_rate_controller_->DidSwapBuffers();
   PostCheckForRetroactiveBeginFrame();
@@ skipping 198 matching lines @@
                "discard_backbuffer", discard_backbuffer);
   // Just ignore the memory manager when it says to set the limit to zero
   // bytes. This will happen when the memory manager thinks that the renderer
   // is not visible (which the renderer knows better).
   if (policy.bytes_limit_when_visible)
     client_->SetMemoryPolicy(policy);
   client_->SetDiscardBackBufferWhenNotVisible(discard_backbuffer);
 }
 
 }  // namespace cc