Replace scoped_ptr with unique_ptr in webrtc/modules/video_coding/

BUG=webrtc:5520

Review URL: https://codereview.webrtc.org/1721353002

Cr-Commit-Position: refs/heads/master@{#11814}
diff --git a/webrtc/modules/video_coding/receiver_unittest.cc b/webrtc/modules/video_coding/receiver_unittest.cc
index 1f3a144..42cc9ac 100644
--- a/webrtc/modules/video_coding/receiver_unittest.cc
+++ b/webrtc/modules/video_coding/receiver_unittest.cc
@@ -10,6 +10,7 @@
 #include <string.h>
 
 #include <list>
+#include <memory>
 #include <queue>
 #include <vector>
 
@@ -84,11 +85,11 @@
     return true;
   }
 
-  rtc::scoped_ptr<SimulatedClock> clock_;
+  std::unique_ptr<SimulatedClock> clock_;
   VCMTiming timing_;
   NullEventFactory event_factory_;
   VCMReceiver receiver_;
-  rtc::scoped_ptr<StreamGenerator> stream_generator_;
+  std::unique_ptr<StreamGenerator> stream_generator_;
 };
 
 TEST_F(TestVCMReceiver, RenderBufferSize_AllComplete) {
@@ -449,8 +450,8 @@
         receiver_(
             &timing_,
             &clock_,
-            rtc::scoped_ptr<EventWrapper>(new FrameInjectEvent(&clock_, false)),
-            rtc::scoped_ptr<EventWrapper>(
+            std::unique_ptr<EventWrapper>(new FrameInjectEvent(&clock_, false)),
+            std::unique_ptr<EventWrapper>(
                 new FrameInjectEvent(&clock_, true))) {}
 
   virtual void SetUp() { receiver_.Reset(); }