Add KillAllBlocking() to android_commands.py.

build/android/pylib/android_commands.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.
 
 """Provides an interface to communicate with the device via the adb command.
 
 Assumes adb binary is currently on system path.
 """
 
 import collections
@@ skipping 451 matching lines @@
       logging.info('\n>>> '.join(result))
     return result
 
   def KillAll(self, process):
     """Android version of killall, connected via adb.
 
     Args:
       process: name of the process to kill off
 
     Returns:
-      the number of processess killed
+      the number of processes killed
     """
     pids = self.ExtractPid(process)
     if pids:
       self.RunShellCommand('kill ' + ' '.join(pids))
     return len(pids)
 
+  def KillAllBlocking(self, process, timeout_sec):
+    """Blocking version of killall, connected via adb.
+
+    This waits until no process matching the corresponding name appears in ps'
+    output anymore.
+
+    Args:
+      process: name of the process to kill off
+      timeout_sec: the timeout in seconds
+
+    Returns:
+      the number of processes killed
+    """
+    processes_killed = self.KillAll(process)
+    if processes_killed:
+      elapsed = 0
+      wait_period = 0.1
+      # Note that this doesn't take into account the time spent in ExtractPid().
+      while self.ExtractPid(process) and elapsed < timeout_sec:
+        time.sleep(wait_period)
+        elapsed += wait_period
+      if elapsed >= timeout_sec:
+        return 0
+    return processes_killed
+
   def StartActivity(self, package, activity, wait_for_completion=False,
                     action='android.intent.action.VIEW',
                     category=None, data=None,
                     extras=None, trace_file_name=None):
     """Starts |package|'s activity on the device.
 
     Args:
       package: Name of package to start (e.g. 'com.google.android.apps.chrome').
       activity: Name of activity (e.g. '.Main' or
         'com.google.android.apps.chrome.Main').
@@ skipping 521 matching lines @@
   """
   def __init__(self, output):
     self._output = output
 
   def write(self, data):
     data = data.replace('\r\r\n', '\n')
     self._output.write(data)
 
   def flush(self):
     self._output.flush()