Replace scoped_ptr with unique_ptr everywhere

But keep #including scoped_ptr.h in .h files, so as not to break
WebRTC users who expect those .h files to give them rtc::scoped_ptr.

BUG=webrtc:5520

Review-Url: https://codereview.webrtc.org/1937693002
Cr-Commit-Position: refs/heads/master@{#12581}
diff --git a/webrtc/test/call_test.h b/webrtc/test/call_test.h
index 41a6b5a..ebc2bb2 100644
--- a/webrtc/test/call_test.h
+++ b/webrtc/test/call_test.h
@@ -82,22 +82,22 @@
 
   Clock* const clock_;
 
-  rtc::scoped_ptr<Call> sender_call_;
-  rtc::scoped_ptr<PacketTransport> send_transport_;
+  std::unique_ptr<Call> sender_call_;
+  std::unique_ptr<PacketTransport> send_transport_;
   VideoSendStream::Config video_send_config_;
   VideoEncoderConfig video_encoder_config_;
   VideoSendStream* video_send_stream_;
   AudioSendStream::Config audio_send_config_;
   AudioSendStream* audio_send_stream_;
 
-  rtc::scoped_ptr<Call> receiver_call_;
-  rtc::scoped_ptr<PacketTransport> receive_transport_;
+  std::unique_ptr<Call> receiver_call_;
+  std::unique_ptr<PacketTransport> receive_transport_;
   std::vector<VideoReceiveStream::Config> video_receive_configs_;
   std::vector<VideoReceiveStream*> video_receive_streams_;
   std::vector<AudioReceiveStream::Config> audio_receive_configs_;
   std::vector<AudioReceiveStream*> audio_receive_streams_;
 
-  rtc::scoped_ptr<test::FrameGeneratorCapturer> frame_generator_capturer_;
+  std::unique_ptr<test::FrameGeneratorCapturer> frame_generator_capturer_;
   test::FakeEncoder fake_encoder_;
   std::vector<std::unique_ptr<VideoDecoder>> allocated_decoders_;
   size_t num_video_streams_;
@@ -127,8 +127,8 @@
   VoiceEngineState voe_recv_;
 
   // The audio devices must outlive the voice engines.
-  rtc::scoped_ptr<test::FakeAudioDevice> fake_send_audio_device_;
-  rtc::scoped_ptr<test::FakeAudioDevice> fake_recv_audio_device_;
+  std::unique_ptr<test::FakeAudioDevice> fake_send_audio_device_;
+  std::unique_ptr<test::FakeAudioDevice> fake_recv_audio_device_;
 };
 
 class BaseTest : public RtpRtcpObserver {