[android] Update FlagChanger to work with additional apks.

build/android/pylib/flag_changer.py

Index: build/android/pylib/flag_changer.py
diff --git a/build/android/pylib/flag_changer.py b/build/android/pylib/flag_changer.py
index 6eb9f0b3c675f93feb2a827fc1aa31f5a8e1fb48..6c4883a76dc3a97fb5b9991b6cbf8b793e51f654 100644
--- a/build/android/pylib/flag_changer.py
+++ b/build/android/pylib/flag_changer.py
@@ -5,12 +5,8 @@
 import constants
 import logging
 import traceback
-import warnings
 
 
-# Location where chrome reads command line flags from
-CHROME_COMMAND_FILE = '/data/local/chrome-command-line'
-
 class FlagChanger(object):
   """Changes the flags Chrome runs with.
 
@@ -21,11 +17,19 @@ class FlagChanger(object):
     once the tests have completed.
   """
 
-  def __init__(self, android_cmd):
-    self._android_cmd = android_cmd
+  def __init__(self, adb,
+               cmdline_file=constants.PACKAGE_INFO['chrome'].cmdline_file):
+    """Initializes the FlagChanger and records the original arguments.
+
+    Args:
+      adb: An instance of AndroidCommands.
+      cmdline_file: Path to the command line file on the device.
+    """
+    self._adb = adb
+    self._cmdline_file = cmdline_file
 
     # Save the original flags.
-    self._orig_line = self._android_cmd.GetFileContents(CHROME_COMMAND_FILE)
+    self._orig_line = self._adb.GetFileContents(self._cmdline_file)
     if self._orig_line:
       self._orig_line = self._orig_line[0].strip()
 
@@ -90,11 +94,12 @@ class FlagChanger(object):
     logging.info('Current flags: %s', self._current_flags)
 
     if self._current_flags:
-      self._android_cmd.SetProtectedFileContents(CHROME_COMMAND_FILE,
-                                        'chrome ' +
-                                        ' '.join(self._current_flags))
+      # The first command line argument doesn't matter as we are not actually
+      # launching the chrome executable using this command line.
+      self._adb.SetProtectedFileContents(self._cmdline_file,
+                                         ' '.join(['_'] + self._current_flags))
     else:
-      self._android_cmd.RunShellCommand('su -c rm ' + CHROME_COMMAND_FILE)
+      self._adb.RunShellCommand('su -c rm ' + self._cmdline_file)
 
   def _TokenizeFlags(self, line):
     """Changes the string containing the command line into a list of flags.
@@ -137,7 +142,7 @@ class FlagChanger(object):
     # Tack on the last flag.
     if not current_flag:
       if within_quotations:
-        warnings.warn("Unterminated quoted string: " + current_flag)
+        logging.warn('Unterminated quoted argument: ' + line)
     else:
       tokenized_flags.append(current_flag)