Clean up PlatformThread.

webrtc/modules/video_render/ios/video_render_ios_gles20.mm

Index: webrtc/modules/video_render/ios/video_render_ios_gles20.mm
diff --git a/webrtc/modules/video_render/ios/video_render_ios_gles20.mm b/webrtc/modules/video_render/ios/video_render_ios_gles20.mm
index 0b4cac1986983c4ba7ca7ee30d054729fb7117e4..6ad5db8b8cbcbc5b64b34b7cf584a7a4b71612c9 100644
--- a/webrtc/modules/video_render/ios/video_render_ios_gles20.mm
+++ b/webrtc/modules/video_render/ios/video_render_ios_gles20.mm
@@ -32,15 +32,15 @@ VideoRenderIosGles20::VideoRenderIosGles20(VideoRenderIosView* view,
       z_order_to_channel_(),
       gles_context_([view context]),
       is_rendering_(true) {
-  screen_update_thread_ = PlatformThread::CreateThread(
-      ScreenUpdateThreadProc, this, "ScreenUpdateGles20");
+  screen_update_thread_.reset(new rtc::PlatformThread(
+      ScreenUpdateThreadProc, this, "ScreenUpdateGles20"));
   screen_update_event_ = EventTimerWrapper::Create();
   GetWindowRect(window_rect_);
 }
 
 VideoRenderIosGles20::~VideoRenderIosGles20() {
   // Signal event to exit thread, then delete it
-  PlatformThread* thread_wrapper = screen_update_thread_.release();
+  rtc::PlatformThread* thread_wrapper = screen_update_thread_.release();
 
   if (thread_wrapper) {
     screen_update_event_->Set();
@@ -83,7 +83,7 @@ int VideoRenderIosGles20::Init() {
   }
 
   screen_update_thread_->Start();
-  screen_update_thread_->SetPriority(kRealtimePriority);
+  screen_update_thread_->SetPriority(rtc::kRealtimePriority);
 
   // Start the event triggering the render process
   unsigned int monitor_freq = 60;