fix test broken issue when using --use-emulator

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 302 matching lines @@
 
   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)
       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 become available.
-    map(lambda buildbot_emulator:buildbot_emulator.ConfirmLaunch(),
+    map(lambda buildbot_emulator:buildbot_emulator.ConfirmLaunch(True),
         buildbot_emulators)
+    # Emulator booting completely is not enough for the test to start.
+    # Wait for another 60 seconds so the emulator can settle down.
+    # Otherwise, the connection to the device may lost during the test,
+    # which will break the test.
+    time.sleep(60)

[John Grabowski, 2012/07/10 06:14:09]

Sadness.
Offhand I don't remember what ConfirmLaunch() does.  But a combination of 'adb
wait-for-device' and a WaitForPackageManager() should do what you need, yes?
Dislike sleeping.  Is flaky and wasteful.

[Wei James(wistoch), 2012/07/10 14:26:48]

ConfirmLaunch() is to make sure the emulator launched before the test starts. 

when the emulator starts, there are several steps. 
1. device offline
2. device online
3. flag dev.bootcomplete set to 1
4. flag sys.boot_completed set to 1

Previously, emulator launch will wait for step 2(wait-for-device). And if
parameter True passed, it will wait for step 3. 

The issue this patch want to fix is that the connection service manager will
reset all connections just before step 4, which will result in that the adb
server lost the connection to the emulator and so the test is broken. There will
be two possible issues:
1. error: device not found even emulator is there. 
2. adb logcat exits so pexpect return with EOF and no real test executed.  

I tested with WaitForDevicePm() but the connection still lost when the PM is
available. 

sleep(60) after the step 3 can make sure the device boot completely and will not
break the test. 

agree with you that adding sleep(60) is ugly. 
after some investigation, I added a function WaitForSystemBootCompleted in
adb_interface and use this to skip the connection lost issue. I don't  know
whether waiting for step 4 is enough, although I have tested on my machine 
for several times and it works.

   elif options.test_device:
     attached_devices = [options.test_device]
   else:
     attached_devices = android_commands.GetAttachedDevices()
 
   if not attached_devices:
     logging.critical('A device must be attached and online.')
     if options.annotate:
       print '@@@STEP_FAILURE@@@'
     return 1
@@ skipping 137 matching lines @@
   # from all suites, but the buildbot associates the exit status only with the
   # most recent step).
   if options.annotate:
     return 0
   else:
     return failed_tests_count
 
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv))