Don't #define snprintf in VS 2015 builds.

third_party/libexif/libexif.gyp

Index: third_party/libexif/libexif.gyp
diff --git a/third_party/libexif/libexif.gyp b/third_party/libexif/libexif.gyp
index 5b7b452d33756e6c1c530f33c174cfc8d97b3e2a..2d8b2428226894d6140f2aaa4e4d5a04b7e98ba5 100644
--- a/third_party/libexif/libexif.gyp
+++ b/third_party/libexif/libexif.gyp
@@ -83,9 +83,16 @@
               'sources': [
                 'libexif.def',
               ],
+              'conditions': [
+                ['MSVS_VERSION < "2015"', {
+                  'defines': [
+                    # This seems like a hack, but this is what Safari Win does.
+                    # Luckily it is no longer needed/allowed with VS 2015.
+                    'snprintf=_snprintf',
+                  ],
+                }],
+              ],
               'defines': [
-                # This seems like a hack, but this is what WebKit Win does.
-                'snprintf=_snprintf',
                 'inline=__inline',
               ],
               'msvs_disabled_warnings': [