Update to Chromium revision 8cb76f56 (#307671)

- Linux/Mac: Load V8 initial snapshot from external bin files (see http://crbug.com/421063).
- Windows: 8.1 SDK is now required (issue #1470).
- Remove CefDOMDocument::GetSelectionStartNode and GetSelectionEndNode methods(see https://codereview.chromium.org/763043004).
- Rename internal namespace used in base headers to avoid linker conflicts with cef_sandbox.lib.

git-svn-id: https://chromiumembedded.googlecode.com/svn/trunk@1956 5089003a-bbd8-11dd-ad1f-f1f9622dbc98

patch/patches/gyp_331.patch

@@ -1,8 +1,8 @@
 diff --git gyp/generator/ninja.py gyp/generator/ninja.py
-index cfb13fc..132bb8c 100644
+index 5cda5c3..bad5ca3 100644
 --- gyp/generator/ninja.py
 +++ gyp/generator/ninja.py
-@@ -742,7 +742,16 @@ class NinjaWriter:
+@@ -743,7 +743,16 @@ class NinjaWriter(object):
        for path in copy['files']:
          # Normalize the path so trailing slashes don't confuse us.
          path = os.path.normpath(path)