Delete all references to GIT_MODE=True from build

scripts/slave/recipe_modules/skia/api.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 json
 import os
 import re
 import sys
 
@@ skipping 278 matching lines @@
                   cwd=repo_path,
                   infra_step=True)
       self.m.step('git clean',
                   cmd=[git, 'clean', '-d', '-f'],
                   cwd=repo_path,
                   infra_step=True)
 
   def checkout_steps(self):
     """Run the steps to obtain a checkout of Skia."""
     cfg_kwargs = {}
-    cfg_kwargs['GIT_MODE'] = True
     if not self.persistent_checkout:
       # We should've obtained the Skia checkout through isolates, so we don't
       # need to perform the checkout ourselves.
       self.m.path['checkout'] = self.skia_dir
       self.got_revision = self.m.properties['revision']
       return
 
     # Use a persistent gclient cache for Swarming.
     cfg_kwargs['CACHE_DIR'] = self.gclient_cache
 
@@ skipping 574 matching lines @@
     # Don't bother to include role, which is always Test.
     # TryBots are uploaded elsewhere so they can use the same key.
     blacklist = ['role', 'is_trybot']
 
     flat = []
     for k in sorted(self.builder_cfg.keys()):
       if k not in blacklist:
         flat.append(k)
         flat.append(self.builder_cfg[k])
     return flat