Add logging for emulator to debug bot timeout

build/android/pylib/utils/emulator.py

Index: build/android/pylib/utils/emulator.py
diff --git a/build/android/pylib/utils/emulator.py b/build/android/pylib/utils/emulator.py
index 4007f1a2d3059553a65200be31e5ff276d6d8470..8ee498d3e2a9cbc28533e0a50078f33b45f452e5 100644
--- a/build/android/pylib/utils/emulator.py
+++ b/build/android/pylib/utils/emulator.py
@@ -190,6 +190,7 @@ def LaunchTempEmulators(emulator_count, abi, api_level, enable_kvm=False,
   if wait_for_boot:
     for emulator in emulators:
       emulator.ConfirmLaunch(True)
+    logging.info('All emulators are fully booted')
   return emulators
 
 
@@ -462,6 +463,7 @@ class Emulator(object):
       # Now that we checked for obvious problems, wait for a boot complete.
       # Waiting for the package manager is sometimes problematic.
       device.WaitUntilFullyBooted(timeout=self._WAITFORBOOT_TIMEOUT)
+      logging.info('%s is now fully booted', self.avd_name)
 
   def Shutdown(self):
     """Shuts down the process started by launch."""