Provision to start base::SimpleTestTickClock at initial ticks

cc/surfaces/display_scheduler_unittest.cc

 // Copyright 2015 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/surfaces/display_scheduler.h"
 
 #include "base/logging.h"
 #include "base/test/null_task_runner.h"
 #include "base/test/simple_test_tick_clock.h"
 #include "base/trace_event/trace_event.h"
@@ skipping 53 matching lines @@
     return scheduler_begin_frame_deadline_count_;
   }
 
  protected:
   int scheduler_begin_frame_deadline_count_;
 };
 
 class DisplaySchedulerTest : public testing::Test {
  public:
   DisplaySchedulerTest()
-      : now_src_(new base::SimpleTestTickClock()),
+      : now_src_(new base::SimpleTestTickClock(
+            base::TimeTicks() + base::TimeDelta::FromMicroseconds(1))),
         task_runner_(new base::NullTaskRunner),
         client_(new FakeDisplaySchedulerClient),
         scheduler_(new TestDisplayScheduler(client_.get(),
                                             &fake_begin_frame_source_,
                                             task_runner_.get(),
-                                            kMaxPendingSwaps)) {
-    now_src_->Advance(base::TimeDelta::FromMicroseconds(10000));
-  }
+                                            kMaxPendingSwaps)) {}
 
   ~DisplaySchedulerTest() override {}
 
   void SetUp() override { scheduler_->SetRootSurfaceResourcesLocked(false); }
 
   void BeginFrameForTest() {
     base::TimeTicks frame_time = now_src_->NowTicks();
     base::TimeDelta interval = BeginFrameArgs::DefaultInterval();
     base::TimeTicks deadline = frame_time + interval;
     fake_begin_frame_source_.TestOnBeginFrame(
@@ skipping 323 matching lines @@
 
   scheduler_->SetRootSurfaceResourcesLocked(true);
   EXPECT_EQ(count++, scheduler_->scheduler_begin_frame_deadline_count());
 
   scheduler_->OutputSurfaceLost();
   EXPECT_EQ(count++, scheduler_->scheduler_begin_frame_deadline_count());
 }
 
 }  // namespace
 }  // namespace cc