create temp avd when running tests on multiple emulators

build/android/run_tests.py

 #!/usr/bin/env python
 #
 # 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.
 
 """Runs all the native unit tests.
 
 1. Copy over test binary to /data/local on device.
 2. Resources: chrome/unit_tests requires resources (chrome.pak and en-US.pak)
@@ skipping 307 matching lines @@
 
   Returns:
     0 if successful, number of failing tests otherwise.
   """
   attached_devices = []
   buildbot_emulators = []
 
   if options.use_emulator:
     for n in range(options.use_emulator):
       t = TimeProfile('Emulator launch %d' % n)
-      buildbot_emulator = emulator.Emulator(options.fast_and_loose)
+      avd_name =  None
+      if n > 0:
+        # Creates a temporary AVD for the extra emulators.
+        avd_name = 'run_tests_avd_%d' % n
+      buildbot_emulator = emulator.Emulator(avd_name, options.fast_and_loose)
       buildbot_emulator.Launch(kill_all_emulators=n == 0)
       t.Stop()
       buildbot_emulators.append(buildbot_emulator)
       attached_devices.append(buildbot_emulator.device)
     # Wait for all emulators to boot completed.
     map(lambda buildbot_emulator: buildbot_emulator.ConfirmLaunch(True),
         buildbot_emulators)
   elif options.test_device:
     attached_devices = [options.test_device]
   else:
@@ skipping 146 matching lines @@
   # the batch (this happens because the exit status is a sum of all failures
   # from all suites, but the buildbot associates the exit status only with the
   # most recent step).
   if options.exit_code:
     return failed_tests_count
   return 0
 
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv))