- Add a SetPriority method to ThreadWrapper

- Remove 'priority' from CreateThread and related member variables from implementations
- Make supplying a name for threads, non-optional

BUG=
R=magjed@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/44729004

Cr-Commit-Position: refs/heads/master@{#8810}
git-svn-id: http://webrtc.googlecode.com/svn/trunk@8810 4adac7df-926f-26a2-2b94-8c16560cd09d

webrtc/modules/video_render/mac/video_render_nsopengl.mm

@@ -380,7 +380,8 @@ _renderingIsPaused (FALSE),
 _windowRefSuperView(NULL),
 _windowRefSuperViewFrame(NSMakeRect(0,0,0,0))
 {
-    _screenUpdateThread = ThreadWrapper::CreateThread(ScreenUpdateThreadProc, this, kRealtimePriority);
+    _screenUpdateThread = ThreadWrapper::CreateThread(ScreenUpdateThreadProc,
+            this, "ScreenUpdateNSOpenGL");
     _screenUpdateEvent = EventWrapper::Create();
 }
 
@@ -437,6 +438,8 @@ int32_t VideoRenderNSOpenGL::StartRender()
             return -1;
         }
 
+        _screenUpdateThread->SetPriority(kRealtimePriority);
+
         UnlockAGLCntx();
         return 0;
     }
@@ -716,6 +719,7 @@ int VideoRenderNSOpenGL::Init()
     }
 
     _screenUpdateThread->Start();
+    _screenUpdateThread->SetPriority(kRealtimePriority);
 
     // Start the event triggering the render process
     unsigned int monitorFreq = 60;