Fix a bug where a RAII object was created for just one line instead of a block.
Fix a bug where a RAII object was created for just one line instead of a block.

Found by clang:

../../third_party/webrtc/video_engine/vie_render_manager.cc:157:3: error: expression result unused [-Werror,-Wunused-value]
  ViEManagerWriteScoped(*this);
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 error generated.

Review URL: https://webrtc-codereview.appspot.com/599005

git-svn-id: 917f5d3ca488f358c4d40eaec14422cf392ccec9@2309 4adac7df-926f-26a2-2b94-8c16560cd09d

TimothyGu/libilbc,mwgoldsmith/ilbc,mwgoldsmith/libilbc,mwgoldsmith/ilbc,mwgoldsmith/ilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,mwgoldsmith/libilbc,mwgoldsmith/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,mwgoldsmith/libilbc,TimothyGu/libilbc,mwgoldsmith/ilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc