[cc] Calculate the correct latest_confirmed_sequence_number in cc::Scheduler.

cc/test/fake_external_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/test/fake_external_begin_frame_source.h"
 
 #include "base/location.h"
 #include "base/single_thread_task_runner.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "base/time/time.h"
@@ skipping 48 matching lines @@
   DCHECK(obs);
   DCHECK(observers_.find(obs) != observers_.end());
 
   observers_.erase(obs);
   if (observers_.empty())
     begin_frame_task_.Cancel();
   if (client_)
     client_->OnRemoveObserver(obs);
 }
 
+void FakeExternalBeginFrameSource::DidFinishFrame(BeginFrameObserver* obs,
+                                                  const BeginFrameAck& ack) {
+  last_acks_[obs] = ack;
+}
+
 bool FakeExternalBeginFrameSource::IsThrottled() const {
   return true;
 }
 
+BeginFrameArgs FakeExternalBeginFrameSource::CreateBeginFrameArgs(
+    BeginFrameArgs::CreationLocation location,
+    base::SimpleTestTickClock* now_src) {
+  return CreateBeginFrameArgsForTesting(location, source_id(),
+                                        next_begin_frame_number_++, now_src);
+}
+
+BeginFrameArgs FakeExternalBeginFrameSource::CreateBeginFrameArgs(
+    BeginFrameArgs::CreationLocation location) {
+  return CreateBeginFrameArgsForTesting(location, source_id(),
+                                        next_begin_frame_number_++);
+}
+
 void FakeExternalBeginFrameSource::TestOnBeginFrame(
     const BeginFrameArgs& args) {
   DCHECK(CalledOnValidThread());
   current_args_ = args;
-  current_args_.source_id = source_id();
-  current_args_.sequence_number = next_begin_frame_number_++;
   std::set<BeginFrameObserver*> observers(observers_);
   for (auto* obs : observers)
     obs->OnBeginFrame(current_args_);
   if (tick_automatically_)
     PostTestOnBeginFrame();
 }
 
 void FakeExternalBeginFrameSource::PostTestOnBeginFrame() {
   begin_frame_task_.Reset(
       base::Bind(&FakeExternalBeginFrameSource::TestOnBeginFrame,
                  weak_ptr_factory_.GetWeakPtr()));
   base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
-      FROM_HERE, base::Bind(begin_frame_task_.callback(),
-                            CreateBeginFrameArgsForTesting(
-                                BEGINFRAME_FROM_HERE, source_id(),
-                                next_begin_frame_number_)),
+      FROM_HERE,
+      base::Bind(begin_frame_task_.callback(),
+                 CreateBeginFrameArgs(BEGINFRAME_FROM_HERE)),
       base::TimeDelta::FromMilliseconds(milliseconds_per_frame_));
   next_begin_frame_number_++;
 }
 
 }  // namespace cc