[Android] DeviceUtils change to make Install work without md5 binary.

build/android/pylib/device/device_utils.py

 # Copyright 2014 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 a variety of device interactions based on adb.
 
 Eventually, this will be based on adb_wrapper.
 """
 # pylint: disable=unused-argument
 
@@ skipping 800 matching lines @@
   def _GetChangedFilesImpl(self, host_path, device_path):
     real_host_path = os.path.realpath(host_path)
     try:
       real_device_path = self.RunShellCommand(
           ['realpath', device_path], single_line=True, check_return=True)
     except device_errors.CommandFailedError:
       real_device_path = None
     if not real_device_path:
       return [(host_path, device_path)]
 
-    host_hash_tuples = md5sum.CalculateHostMd5Sums([real_host_path])
+    try:

[jbudorick, 2015/04/13 22:51:47]

This should be done in md5sum.py, not in device_utils.py.

Additionally, it should cover both the host calculation and the device
calculation.

[mikecase (-- gone --), 2015/04/14 16:18:38]

Now both the call to md5sum.CalculateHostMd5Sums and
md5sum.CalculateDeviceMd5Sums in device_utils are in the try catch.

In md5sum.py I added a couple lines to check if the necessary files were built,
and if not, raise a IOError with an appropriate message.

+      host_hash_tuples = md5sum.CalculateHostMd5Sums([real_host_path])
+    except EnvironmentError:
+      logging.info('md5sum_bin_host might not be built, '
+                   'or we might not be able to find it.')
+      return [(host_path, device_path)]
+
     device_paths_to_md5 = (
         real_device_path if os.path.isfile(real_host_path)
         else ('%s/%s' % (real_device_path, os.path.relpath(p, real_host_path))
               for _, p in host_hash_tuples))
     device_hash_tuples = md5sum.CalculateDeviceMd5Sums(
         device_paths_to_md5, self)
 
     if os.path.isfile(host_path):
       if (not device_hash_tuples
           or device_hash_tuples[0].hash != host_hash_tuples[0].hash):
@@ skipping 699 matching lines @@
     """Returns client cache."""
     if client_name not in self._client_caches:
       self._client_caches[client_name] = {}
     return self._client_caches[client_name]
 
   def _ClearCache(self):
     """Clears all caches."""
     for client in self._client_caches:
       self._client_caches[client].clear()
     self._cache.clear()