Revert "Fix Omnibox.CharTypedToRepaintLatency regression with D3DVsync experiment"

cc/scheduler/begin_frame_source.cc

 // Copyright 2014 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/scheduler/begin_frame_source.h"
 
 #include <stddef.h>
 
 #include "base/atomic_sequence_num.h"
 #include "base/auto_reset.h"
@@ skipping 265 matching lines @@
   DCHECK(obs);
   DCHECK(observers_.find(obs) == observers_.end());
 
   bool observers_was_empty = observers_.empty();
   observers_.insert(obs);
   obs->OnBeginFrameSourcePausedChanged(paused_);
   if (observers_was_empty)
     client_->OnNeedsBeginFrames(true);
 
   // Send a MISSED begin frame if necessary.
-  BeginFrameArgs missed_args = GetMissedBeginFrameArgs(obs);
-  if (missed_args.IsValid()) {
-    DCHECK_EQ(BeginFrameArgs::MISSED, missed_args.type);
-    obs->OnBeginFrame(missed_args);
+  if (last_begin_frame_args_.IsValid()) {
+    const BeginFrameArgs& last_args = obs->LastUsedBeginFrameArgs();
+    if (!last_args.IsValid() ||
+        (last_begin_frame_args_.frame_time > last_args.frame_time)) {
+      DCHECK(
+          (last_begin_frame_args_.source_id != last_args.source_id) ||
+          (last_begin_frame_args_.sequence_number > last_args.sequence_number))
+          << "current " << last_begin_frame_args_.AsValue()->ToString()
+          << ", last " << last_args.AsValue()->ToString();
+      BeginFrameArgs missed_args = last_begin_frame_args_;
+      missed_args.type = BeginFrameArgs::MISSED;
+      obs->OnBeginFrame(missed_args);
+    }
   }
 }
 
 void ExternalBeginFrameSource::RemoveObserver(BeginFrameObserver* obs) {
   DCHECK(obs);
   DCHECK(observers_.find(obs) != observers_.end());
 
   observers_.erase(obs);
-  if (observers_.empty())
+  if (observers_.empty()) {
+    last_begin_frame_args_ = BeginFrameArgs();
     client_->OnNeedsBeginFrames(false);
+  }
 }
 
 bool ExternalBeginFrameSource::IsThrottled() const {
   return true;
 }
 
 void ExternalBeginFrameSource::OnSetBeginFrameSourcePaused(bool paused) {
   if (paused_ == paused)
     return;
   paused_ = paused;
@@ skipping 13 matching lines @@
     if (!last_args.IsValid() || (args.frame_time > last_args.frame_time)) {
       DCHECK((args.source_id != last_args.source_id) ||
              (args.sequence_number > last_args.sequence_number))
           << "current " << args.AsValue()->ToString() << ", last "
           << last_args.AsValue()->ToString();
       obs->OnBeginFrame(args);
     }
   }
 }
 
-BeginFrameArgs ExternalBeginFrameSource::GetMissedBeginFrameArgs(
-    BeginFrameObserver* obs) {
-  if (!last_begin_frame_args_.IsValid())
-    return BeginFrameArgs();
-
-  const BeginFrameArgs& last_args = obs->LastUsedBeginFrameArgs();
-  if (last_args.IsValid() &&
-      last_begin_frame_args_.frame_time <= last_args.frame_time) {
-    return BeginFrameArgs();
-  }
-
-  DCHECK((last_begin_frame_args_.source_id != last_args.source_id) ||
-         (last_begin_frame_args_.sequence_number > last_args.sequence_number))
-      << "current " << last_begin_frame_args_.AsValue()->ToString() << ", last "
-      << last_args.AsValue()->ToString();
-  BeginFrameArgs missed_args = last_begin_frame_args_;
-  missed_args.type = BeginFrameArgs::MISSED;
-  return missed_args;
-}
-
 }  // namespace cc