Use Systrace tracing controller in profile_chrome

systrace/profile_chrome/ddms_tracing_agent.py

Index: systrace/profile_chrome/ddms_tracing_agent.py
diff --git a/systrace/profile_chrome/ddms_tracing_agent.py b/systrace/profile_chrome/ddms_tracing_agent.py
index 158e45b27fc74ea05486e073d4d83ac027d4b3a6..276a3b9fb055a92ef9b11770fed647a8dd82b803 100644
--- a/systrace/profile_chrome/ddms_tracing_agent.py
+++ b/systrace/profile_chrome/ddms_tracing_agent.py
@@ -41,10 +41,12 @@ class DdmsAgent(tracing_agents.TracingAgent):
       cmd += '--sampling %d ' % _DDMS_SAMPLING_FREQUENCY_US
     cmd += '%s %s' % (self._package, self._output_file)
     self._device.RunShellCommand(cmd)
+    return True
 
   @py_utils.Timeout(tracing_agents.START_STOP_TIMEOUT)
   def StopAgentTracing(self, timeout=None):
     self._device.RunShellCommand('am profile stop %s' % self._package)
+    return True
 
   @py_utils.Timeout(tracing_agents.GET_RESULTS_TIMEOUT)
   def GetResults(self, timeout=None):
@@ -65,15 +67,24 @@ class DdmsAgent(tracing_agents.TracingAgent):
     return False
 
   def RecordClockSyncMarker(self, sync_id, did_record_sync_marker_callback):
+    # pylint: disable=unused-argument
     assert self.SupportsExplicitClockSync(), ('Clock sync marker cannot be '
         'recorded since explicit clock sync is not supported.')
 
 
 class DdmsConfig(tracing_agents.TracingConfig):
-  def __init__(self):
+  def __init__(self, device, package_info, ddms):
     tracing_agents.TracingConfig.__init__(self)
+    self.device = device
+    self.package_info = package_info
+    self.ddms = ddms
 
 
+def try_create_agent(config):
+  if config.ddms:
+    return DdmsAgent(config.device, config.package_info)
+  return None
+
 def add_options(parser):
   options = optparse.OptionGroup(parser, 'Java tracing')
   options.add_option('--ddms', help='Trace Java execution using DDMS '
@@ -81,5 +92,4 @@ def add_options(parser):
   return options
 
 def get_config(options):
-  # pylint: disable=unused-argument
-  return DdmsConfig()
+  return DdmsConfig(options.device, options.package_info, options.ddms)