enable speed optimization for libyuv

BUG=439
TESTED=out\release\libyuv_unittest --gtest_filter=*I420ToARGB_Opt
R=bcornell@google.com

Review URL: https://webrtc-codereview.appspot.com/55389004

git-svn-id: http://libyuv.googlecode.com/svn/trunk@1405 16f28f9a-4ce2-e073-06de-1de4eb20be90

README.chromium

 Name: libyuv
 URL: http://code.google.com/p/libyuv/
-Version: 1404
+Version: 1405
 License: BSD
 License File: LICENSE
 

include/libyuv/version.h

@@ -11,6 +11,6 @@
 #ifndef INCLUDE_LIBYUV_VERSION_H_  // NOLINT
 #define INCLUDE_LIBYUV_VERSION_H_
 
-#define LIBYUV_VERSION 1404
+#define LIBYUV_VERSION 1405
 
 #endif  // INCLUDE_LIBYUV_VERSION_H_  NOLINT

libyuv.gyp

@@ -93,6 +93,9 @@
       'target_name': 'libyuv',
       # Change type to 'shared_library' to build .so or .dll files.
       'type': 'static_library',
+      'variables': {
+        'optimize': 'max',  # enable O2 and ltcg.
+      },
       # Allows libyuv.a redistributable library without external dependencies.
       'standalone_static_library': 1,
       'conditions': [