gyp: only include windows *_x64 targets if GYP_GENERATORS includes ninja

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 73 matching lines @@
               },
               '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
           # OK for us to just make these inherit non-archwidth-specific
           # configurations without modification.
-          'Debug_x64': {
-            'inherit_from': ['Debug'],
-          },
-          'Release_x64': {
-            'inherit_from': ['Release'],
-          },
-          'Release_Developer_x64': {
-            'inherit_from': ['Release_Developer'],
-          },
-        },
-        'conditions' : [
+          #
+          # See http://skbug.com/2442 : These targets cause problems in the
+          # MSVS build, so only include them if gyp is generating a ninja build.
+          [ '"ninja" in "<!(echo %GYP_GENERATORS%)"', {
+            'configurations': {
+              'Debug_x64': {
+                'inherit_from': ['Debug'],
+              },
+              'Release_x64': {
+                'inherit_from': ['Release'],
+              },
+              'Release_Developer_x64': {
+                'inherit_from': ['Release_Developer'],
+              },
+            },
+          }],
           [ 'skia_arch_width == 64', {
             'msvs_configuration_platform': 'x64',
           }],
           [ 'skia_arch_width == 32', {
             'msvs_configuration_platform': 'Win32',
           }],
           [ 'skia_warnings_as_errors', {
             'msvs_settings': {
               'VCCLCompilerTool': {
                 'WarnAsError': 'true',
@@ skipping 487 matching lines @@
       'defines': [
         'SK_USE_POSIX_THREADS',
       ],
     }],
   ], # end 'conditions'
   # The Xcode SYMROOT must be at the root. See build/common.gypi in chromium for more details
   'xcode_settings': {
     'SYMROOT': '<(DEPTH)/xcodebuild',
   },
 }