Add comments to gyp showing what the macros are for.

BUG=189
TEST=none
Review URL: https://webrtc-codereview.appspot.com/1113007

git-svn-id: http://libyuv.googlecode.com/svn/trunk@586 16f28f9a-4ce2-e073-06de-1de4eb20be90

README.chromium

 Name: libyuv
 URL: http://code.google.com/p/libyuv/
-Version: 585
+Version: 586
 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 585
+#define LIBYUV_VERSION 586
 
 #endif  // INCLUDE_LIBYUV_VERSION_H_  NOLINT

libyuv.gyp

@@ -30,9 +30,11 @@
       ],
       'defines': [
         'HAVE_JPEG',
+	# Enable the following 3 macros to turn off assembly for specified CPU.
         # 'LIBYUV_DISABLE_X86',
         # 'LIBYUV_DISABLE_NEON',
         # 'LIBYUV_DISABLE_MIPS',
+	# Enable the following macro to build libyuv as a shared library (dll).
         # 'LIBYUV_BUILDING_SHARED_LIBRARY',
       ],
       'include_dirs': [

libyuv_test.gyp

@@ -19,9 +19,11 @@
       ],
       'defines': [
         'LIBYUV_SVNREVISION="<!(svnversion -n)"',
+	# Enable the following 3 macros to turn off assembly for specified CPU.
         # 'LIBYUV_DISABLE_X86',
         # 'LIBYUV_DISABLE_NEON',
         # 'LIBYUV_DISABLE_MIPS',
+	# Enable the following macro to build libyuv as a shared library (dll).
         # 'LIBYUV_USING_SHARED_LIBRARY',
       ],
       'sources': [

unit_test/planar_test.cc

@@ -1161,4 +1161,3 @@ TEST_F(libyuvTest, ARGBSubtract_Opt) {
 }
 
 }  // namespace libyuv
-