Update bisect script to handle deleted .DEPS.git from chromium source

tools/auto_bisect/bisect_utils.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.
 
 """Utility functions used by the bisect tool.
 
 This includes functions related to checking out the depot and outputting
 annotations for the Buildbot waterfall.
 """
 
@@ skipping 267 matching lines @@
   spec = ''.join([l for l in spec.splitlines()])
 
   if 'android' in opts.target_platform:
     spec += GCLIENT_SPEC_ANDROID
 
   return_code = RunGClient(
       ['config', '--spec=%s' % spec], cwd=cwd)
   return return_code
 
 
-def IsDepsFileBlink():
+def IsDepsFileBlink(git_revision=''):
   """Reads .DEPS.git and returns whether or not we're using blink.
 
+  Args:
+    git_revision: A git hash revision of chromium.
   Returns:
     True if blink, false if webkit.
   """
-  locals = {
+  git_cmd = ['cat-file', 'blob', '%s:%s' %(git_revision, FILE_DEPS_GIT)]
+  search_str = 'blink.git'
+  search_key = 'webkit_url'
+  (out_put, ret_val) = RunGit(git_cmd)
+  if ret_val:
+    search_str = 'blink'
+    search_key = 'webkit_trunk'
+    git_cmd = ['cat-file', 'blob', '%s:%s' %(git_revision, 'FILE_DEPS')]
+    (out_put, ret_val) = RunGit(git_cmd)
+    if ret_val:
+      print 'Error processing DEPS or .DEPS.git'
+      return False
+  locals =  {
       'Var': lambda _: locals["vars"][_],
       'From': lambda *args: None
   }
-  execfile(FILE_DEPS_GIT, {}, locals)
-  return 'blink.git' in locals['vars']['webkit_url']
+
+  exec out_put in  {}, locals
+
+  return search_str in locals['vars'][search_key]
 
 
 def OnAccessError(func, path, _):
   """Error handler for shutil.rmtree.
 
   Source: http://goo.gl/DEYNCT
 
   If the error is due to an access error (read only file), it attempts to add
   write permissions, then retries.
 
@@ skipping 280 matching lines @@
   return sys.platform.startswith('linux')
 
 
 def IsMacHost():
   """Checks whether or not the script is running on Mac.
 
   Returns:
     True if running on Mac.
   """
   return sys.platform.startswith('darwin')