Make LTCG optional on windows builds.

gyp/common_conditions.gypi

 # conditions used in both common.gypi and skia.gyp in chromium
 #
 {
   'defines': [
     'SK_ALLOW_STATIC_GLOBAL_INITIALIZERS=<(skia_static_initializers)',
     'SK_SUPPORT_GPU=<(skia_gpu)',
     'SK_SUPPORT_OPENCL=<(skia_opencl)',
     'SK_FORCE_DISTANCEFIELD_FONTS=<(skia_force_distancefield_fonts)',
   ],
   'conditions' : [
@@ skipping 68 matching lines @@
                 'GenerateDebugInformation': 'true', # /DEBUG
                 'LinkIncremental': '2',             # /INCREMENTAL
               },
             },
           },
           'Release': {
             'msvs_settings': {
               'VCCLCompilerTool': {
                 'DebugInformationFormat': '3',      # programDatabase (/Zi)
                 'Optimization': '<(skia_release_optimization_level)',
-                'WholeProgramOptimization': 'true', #/GL
                # Changing the floating point model requires rebaseling gm images
                #'FloatingPointModel': '2',          # fast (/fp:fast)
                 'FavorSizeOrSpeed': '1',            # speed (/Ot)
                 'PreprocessorDefinitions': ['NDEBUG'],
                 'RuntimeLibrary': '2',              # rtMultiThreadedDLL (/MD)
                 'EnableEnhancedInstructionSet': '2',# /arch:SSE2
                 'RuntimeTypeInfo': 'false',         # /GR-
               },
               'VCLinkerTool': {
                 'GenerateDebugInformation': 'true', # /DEBUG
-                'LinkTimeCodeGeneration': '1',      # useLinkTimeCodeGeneration /LTCG
-              },
-              'VCLibrarianTool': {
-                'LinkTimeCodeGeneration': 'true',   # useLinkTimeCodeGeneration /LTCG
               },
             },
           },
         },
         'conditions' : [
           # Gyp's ninja generator depends on these specially named
           # configurations to build 64-bit on Windows.
           # See http://skbug.com/2348
           #
           # We handle the 64- vs 32-bit variations elsewhere, so I think it's
@@ skipping 33 matching lines @@
           }],
           [ 'skia_win_exceptions', {
             'msvs_settings': {
               'VCCLCompilerTool': {
                 'AdditionalOptions': [
                   '/EHsc',
                 ],
               },
             },
           }],
+          [ 'skia_win_ltcg', {

[mtklein, 2014/06/26 19:00:50]

Even skia_ltcg or just ltcg?  I'm not really sure why we prefix everything with
skia_.

+            'configurations': {
+              'Release': {
+                'msvs_settings': {
+                  'VCCLCompilerTool': {
+                    'WholeProgramOptimization': 'true', #/GL
+                  },
+                  'VCLinkerTool': {
+                    'LinkTimeCodeGeneration': '1',      # useLinkTimeCodeGeneration /LTCG
+                  },
+                  'VCLibrarianTool': {
+                    'LinkTimeCodeGeneration': 'true',   # useLinkTimeCodeGeneration /LTCG
+                  },
+                },
+              },
+            },
+          }],
         ],
       },
     ],
 
     # The following section is common to linux + derivatives and android
     [ 'skia_os in ["linux", "freebsd", "openbsd", "solaris", "nacl", "chromeos", "android"]',
       {
         'cflags': [
           '-g',
           '-fno-exceptions',
@@ skipping 510 matching lines @@
         # add flags here (e.g. SK_SUPPORT_LEGACY_...) needed by moz2d
       ],
     }],
 
   ], # end 'conditions'
   # The Xcode SYMROOT must be at the root. See build/common.gypi in chromium for more details
   'xcode_settings': {
     'SYMROOT': '<(DEPTH)/xcodebuild',
   },
 }