Convert //cc from scoped_ptr to std::unique_ptr.

cc/scheduler/compositor_timing_history_unittest.cc

Index: cc/scheduler/compositor_timing_history_unittest.cc
diff --git a/cc/scheduler/compositor_timing_history_unittest.cc b/cc/scheduler/compositor_timing_history_unittest.cc
index f57d44340c5a3a51b83472e2378afdbaea6d9a76..8bbe93d999c54e1cd98ed2f8bb8dd324c73f11f8 100644
--- a/cc/scheduler/compositor_timing_history_unittest.cc
+++ b/cc/scheduler/compositor_timing_history_unittest.cc
@@ -43,7 +43,7 @@ class CompositorTimingHistoryTest : public testing::Test {
   base::TimeTicks Now() { return now_; }
 
  protected:
-  scoped_ptr<RenderingStatsInstrumentation> rendering_stats_;
+  std::unique_ptr<RenderingStatsInstrumentation> rendering_stats_;
   TestCompositorTimingHistory timing_history_;
   base::TimeTicks now_;
 };