Remove references to tryserver.chromium.gpu

PRESUBMIT.py

 # Copyright (c) 2012 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.
 
 """Top-level presubmit script for Chromium.
 
 See http://dev.chromium.org/developers/how-tos/depottools/presubmit-scripts
 for more details about the presubmit API built into depot_tools.
 """
 
@@ skipping 1680 matching lines @@
   and return None.  There is no longer a default master.
   """
   # Potentially ambiguous bot names are listed explicitly.
   master_map = {
       'chromium_presubmit': 'tryserver.chromium.linux',
       'blink_presubmit': 'tryserver.chromium.linux',
       'tools_build_presubmit': 'tryserver.chromium.linux',
   }
   master = master_map.get(bot)
   if not master:
-    if 'gpu' in bot:
-      master = 'tryserver.chromium.gpu'
-    elif 'linux' in bot or 'android' in bot or 'presubmit' in bot:
+    if 'linux' in bot or 'android' in bot or 'presubmit' in bot:
       master = 'tryserver.chromium.linux'
     elif 'win' in bot:
       master = 'tryserver.chromium.win'
     elif 'mac' in bot or 'ios' in bot:
       master = 'tryserver.chromium.mac'
   return master
 
 
 def GetDefaultTryConfigs(bots):
   """Returns a list of ('bot', set(['tests']), filtered by [bots].
@@ skipping 45 matching lines @@
     # Explicitly iterate over copies of dicts since we mutate them.
     for master in builders.keys():
       for builder in builders[master].keys():
         # Do not trigger presubmit builders, since they're likely to fail
         # (e.g. OWNERS checks before finished code review), and we're
         # running local presubmit anyway.
         if 'presubmit' in builder:
           builders[master].pop(builder)
 
   return builders