For xcode disable pch option so includes will use the .h instead of expecting a .pch.

BUG=none
TESTED=untested
R=noahric@chromium.org

Review URL: https://webrtc-codereview.appspot.com/18239004

git-svn-id: http://libyuv.googlecode.com/svn/trunk@1059 16f28f9a-4ce2-e073-06de-1de4eb20be90

README.chromium

@@ -1,6 +1,6 @@
 Name: libyuv
 URL: http://code.google.com/p/libyuv/
-Version: 1058
+Version: 1059
 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 1058
+#define LIBYUV_VERSION 1059
 
 #endif  // INCLUDE_LIBYUV_VERSION_H_  NOLINT

libyuv.gyp

@@ -10,6 +10,12 @@
   'includes': [
     'libyuv.gypi',
   ],
+  # Make sure that if we are being compiled to an xcodeproj, nothing tries to
+  # include a .pch.
+  'xcode_settings': {
+    'GCC_PREFIX_HEADER': '',
+    'GCC_PRECOMPILE_PREFIX_HEADER': 'NO',
+  },
   'variables': {
     'use_system_libjpeg%': 0,
     'libyuv_disable_jpeg%': 0,