<third_party/WebKit> FIXUP: Prevent a python IOError on Windows

The bison script for compiling grammars suffers from the MAX_PATH IOError
issue on Windows. This occurs when doing a shadow build that results in
large relative paths in the generated GYP actions.

Change-Id: Ic875a818ee0cda85efcb3ccebaf885872aed8746
Reviewed-by: Michael Bruning <michael.bruning@digia.com>
Reviewed-by: Jarred Nicholls <jarred.nicholls@gmail.com>

chromium/third_party/WebKit/Source/build/scripts/rule_bison.py

@@ -41,11 +41,12 @@ import os
 import os.path
 import subprocess
 import sys
+from utilities import abs
 
 assert len(sys.argv) == 3 or len(sys.argv) == 4
 
-inputFile = sys.argv[1]
-outputDir = sys.argv[2]
+inputFile = abs(sys.argv[1])
+outputDir = abs(sys.argv[2])
 bisonExe = 'bison'
 if len(sys.argv) > 3:
     bisonExe = sys.argv[3]

chromium/third_party/WebKit/Source/build/scripts/utilities.py

+# Copyright 2014 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.
+
+import os
+
+def abs(filename):
+    # open, abspath, etc. are all limited to the 260 char MAX_PATH and this causes
+    # problems when we try to resolve long relative paths in the WebKit directory structure.
+    return os.path.normpath(os.path.join(os.getcwd(), filename))