Clean up PRESUBMIT.py - remove references to removed clang trybots

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 gcl.
 """
 
@@ skipping 1696 matching lines @@
       'android_arm64_dbg_recipe',
       'android_chromium_gn_compile_rel',
       'android_chromium_gn_compile_dbg',
       'android_clang_dbg',
       'android_clang_dbg_recipe',
       'android_dbg_tests_recipe',
       'ios_dbg_simulator',
       'ios_rel_device',
       'ios_rel_device_ninja',
       'linux_chromium_chromeos_rel',
-      'linux_chromium_clang_dbg',
       'linux_chromium_gn_dbg',
       'linux_chromium_gn_rel',
       'linux_chromium_rel_ng',
       'linux_gpu',
       'mac_chromium_compile_dbg',
       'mac_chromium_rel_ng',
       'mac_gpu',
       'win_chromium_compile_dbg',
       'win_chromium_rel_ng',
       'win_chromium_x64_rel_ng',
       'win_gpu',
       'win8_chromium_rel',
   ]
 
   # Match things like path/aura/file.cc and path/file_aura.cc.
   # Same for chromeos.
   if any(re.search(r'[\\\/_](aura|chromeos)', f) for f in files):
     builders.extend([
         'linux_chromeos_asan',
-        'linux_chromium_chromeos_clang_dbg'
     ])
 
   # If there are gyp changes to base, build, or chromeos, run a full cros build
   # in addition to the shorter linux_chromeos build. Changes to high level gyp
   # files have a much higher chance of breaking the cros build, which is
   # differnt from the linux_chromeos build that most chrome developers test
   # with.
   if any(re.search('^(base|build|chromeos).*\.gypi?$', f) for f in files):
     builders.extend(['cros_x86'])
 
   # The AOSP bot doesn't build the chrome/ layer, so ignore any changes to it
   # unless they're .gyp(i) files as changes to those files can break the gyp
   # step on that bot.
   if (not all(re.search('^chrome', f) for f in files) or
       any(re.search('\.gypi?$', f) for f in files)):
     builders.extend(['android_aosp'])
 
   return GetDefaultTryConfigs(builders)