Refactor Skia's GYP to separate Chrome additions from the core lib.

skia/skia_common.gypi

Index: skia/skia_common.gypi
diff --git a/skia/skia_common.gypi b/skia/skia_common.gypi
new file mode 100644
index 0000000000000000000000000000000000000000..616ae5bb31b33fc87048b0605102020a87cf7026
--- /dev/null
+++ b/skia/skia_common.gypi
@@ -0,0 +1,33 @@
+# Copyright 2013 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# This gypi file handles the removal of platform-specific files from the
+# Skia build.
+{
+  'conditions': [
+    [ 'OS != "android"', {
+      'sources/': [
+         ['exclude', '_android\\.(cc|cpp)$'],
+      ],
+    }],
+    [ 'OS != "ios"', {
+      'sources/': [
+         ['exclude', '_ios\\.(cc|cpp|mm?)$'],
+      ],
+    }],
+    [ 'OS != "mac"', {
+      'sources/': [
+        ['exclude', '_mac\\.(cc|cpp|mm?)$'],
+      ],
+    }],
+    [ 'OS != "win"', {
+      'sources/': [ ['exclude', '_win\\.(cc|cpp)$'] ],
+    }],
+    [ 'use_glib == 0', {
+      'sources/': [ ['exclude', '_linux\\.(cc|cpp)$'] ],
+    }],
+  ],
+
+  'msvs_disabled_warnings': [4244, 4267, 4341, 4345, 4390, 4554, 4748, 4800],
+}