Remove external begin frame source parameter and settings

cc/scheduler/scheduler_unittest.cc

 // Copyright 2011 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/scheduler.h"
 
 #include <stddef.h>
 
 #include <string>
 #include <vector>
@@ skipping 249 matching lines @@
         frame_source = synthetic_frame_source_.get();
         break;
     }
     DCHECK(frame_source);
 
     std::unique_ptr<FakeCompositorTimingHistory>
         fake_compositor_timing_history = FakeCompositorTimingHistory::Create(
             scheduler_settings_.using_synchronous_renderer_compositor);
     fake_compositor_timing_history_ = fake_compositor_timing_history.get();
 
-    scheduler_.reset(
-        new TestScheduler(now_src_.get(), client_.get(), scheduler_settings_, 0,
-                          task_runner_.get(), frame_source,
-                          std::move(fake_compositor_timing_history)));
-    DCHECK(scheduler_);
+    scheduler_.reset(new TestScheduler(
+        now_src_.get(), client_.get(), scheduler_settings_, 0,
+        task_runner_.get(), std::move(fake_compositor_timing_history)));
+    scheduler_->SetBeginFrameSource(frame_source);
     client_->set_scheduler(scheduler_.get());
 
     // Use large estimates by default to avoid latency recovery in most tests.
     fake_compositor_timing_history_->SetAllEstimatesTo(kSlowDuration);
 
     return scheduler_.get();
   }
 
   void SetUpScheduler(BeginFrameSourceType bfs_type,
                       std::unique_ptr<FakeSchedulerClient> client) {
@@ skipping 3320 matching lines @@
 }
 
 TEST_F(SchedulerTest, BeginMainFrameOnCriticalPath_AHS) {
   EXPECT_FALSE(BeginMainFrameOnCriticalPath(
       SMOOTHNESS_TAKES_PRIORITY,
       ScrollHandlerState::SCROLL_AFFECTS_SCROLL_HANDLER, kSlowDuration));
 }
 
 }  // namespace
 }  // namespace cc