YuvPixel for llvm use byte clamping branchless instead of int expression.

BUG=221
TEST=I420To*R*
Review URL: https://webrtc-codereview.appspot.com/1313011

git-svn-id: http://libyuv.googlecode.com/svn/trunk@676 16f28f9a-4ce2-e073-06de-1de4eb20be90

README.chromium

 Name: libyuv
 URL: http://code.google.com/p/libyuv/
-Version: 675
+Version: 676
 License File: LICENSE
 
 Description:

include/libyuv/version.h

@@ -11,6 +11,6 @@
 #ifndef INCLUDE_LIBYUV_VERSION_H_  // NOLINT
 #define INCLUDE_LIBYUV_VERSION_H_
 
-#define LIBYUV_VERSION 675
+#define LIBYUV_VERSION 676
 
 #endif  // INCLUDE_LIBYUV_VERSION_H_  NOLINT