Revert of [Android] Don't use a device blacklist if one isn't provided.

build/android/devil/android/device_blacklist.py

Index: build/android/devil/android/device_blacklist.py
diff --git a/build/android/devil/android/device_blacklist.py b/build/android/devil/android/device_blacklist.py
index 615b3e6bea5fef2f4ca6a522cdc7c4656d0862cc..0724654be7b9b5575eb551ce9eda7cb82ca5e095 100644
--- a/build/android/devil/android/device_blacklist.py
+++ b/build/android/devil/android/device_blacklist.py
@@ -3,7 +3,6 @@
 # found in the LICENSE file.
 
 import json
-import logging
 import os
 import threading
 
@@ -50,16 +49,34 @@
     Args:
       devices: list of bad devices to be added to the blacklist file.
     """
-    logging.info('Adding %s to blacklist %s', ','.join(devices), self._path)
     with self._blacklist_lock:
-      blacklist = self.Read()
+      blacklist = ReadBlacklist()
       blacklist.extend(devices)
-      self.Write(blacklist)
+      WriteBlacklist(blacklist)
 
   def Reset(self):
     """Erases the blacklist file if it exists."""
-    logging.info('Resetting blacklist %s', self._path)
     with self._blacklist_lock:
       if os.path.exists(self._path):
         os.remove(self._path)
 
+
+def ReadBlacklist():
+  # TODO(jbudorick): Phase out once all clients have migrated.
+  return Blacklist(BLACKLIST_JSON).Read()
+
+
+def WriteBlacklist(blacklist):
+  # TODO(jbudorick): Phase out once all clients have migrated.
+  Blacklist(BLACKLIST_JSON).Write(blacklist)
+
+
+def ExtendBlacklist(devices):
+  # TODO(jbudorick): Phase out once all clients have migrated.
+  Blacklist(BLACKLIST_JSON).Extend(devices)
+
+
+def ResetBlacklist():
+  # TODO(jbudorick): Phase out once all clients have migrated.
+  Blacklist(BLACKLIST_JSON).Reset()
+