Add unit_tests bundle as a default compile target for Android.

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 492 matching lines @@
   if not files:
     return []
 
   if all(re.search('\.(m|mm)$|[/_]mac[/_.]', f) for f in files):
     return ['mac_rel']
   if all(re.search('[/_]win[/_.]', f) for f in files):
     return ['win_rel']
   if all(re.search('[/_]android[/_.]', f) for f in files):
     return ['android']
 
-  trybots = ['win_rel', 'linux_rel', 'mac_rel', 'linux_clang:compile']
+  trybots = ['win_rel', 'linux_rel', 'mac_rel', 'linux_clang:compile',
+             'android']
   # match things like aurax11.cc or aura_oak.cc
   if any(re.search('[/_]aura', f) for f in files):
     trybots.append('linux_chromeos')
 
-  if not all(f.startswith('chrome/') for f in files):
-    trybots.append('android')
-
   return trybots