Enable chromium_code=1 on Windows

Source/config.gyp

Index: Source/config.gyp
diff --git a/Source/config.gyp b/Source/config.gyp
index 52da069c6d3ef4155e06adf19c86eb2c2f79ade3..b223facfd7908a39922b003642882f5268a25676 100644
--- a/Source/config.gyp
+++ b/Source/config.gyp
@@ -43,8 +43,11 @@
         '..',
       ],
       'msvs_disabled_warnings': [
-        4138, 4244, 4291, 4305, 4344, 4355, 4521, 4099,
+        4138, 4244, 4291, 4305, 4344, 4355, 4521, 4099, 4800, 4996, 4714,
       ],
+      'variables': {
+        'chromium_code': 1,
+      },
       'conditions': [
         ['OS=="win" and component=="shared_library"', {
           'defines': [
@@ -89,12 +92,6 @@
           # timesNewRoman.unstatic.3258 and colorTransparent.unstatic.4879.
           'cflags': ['-Wno-uninitialized'],
         }],
-        ['OS!="win"', {
-          # TODO: Turn this on on all platforms, http://crbug.com/312287
-          'variables': {
-            'chromium_code': 1,
-          },
-        }],
         ['clang==1', {
           'cflags': ['-Wglobal-constructors'],
           'xcode_settings': {