telemetry: Added timeout parameter to StartTracing.

tools/telemetry/telemetry/core/browser.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.
 
 import os
 
 from telemetry.core import browser_credentials
 from telemetry.core import extension_dict
 from telemetry.core import platform
 from telemetry.core import tab_list
@@ skipping 195 matching lines @@
     self._active_profilers.append(
         profiler_class(self._browser_backend, self._platform_backend,
             base_output_file))
 
   def StopProfiling(self):
     """Stops all active profilers and saves their results."""
     for profiler in self._active_profilers:
       profiler.CollectProfile()
     self._active_profilers = []
 
-  def StartTracing(self, custom_categories=None):
-    return self._browser_backend.StartTracing(custom_categories)
+  def StartTracing(self, custom_categories=None, timeout=10):
+    return self._browser_backend.StartTracing(custom_categories, timeout)
 
   def StopTracing(self):
     return self._browser_backend.StopTracing()
 
   def GetTraceResultAndReset(self):
     """Returns the result of the trace, as TraceResult object."""
     return self._browser_backend.GetTraceResultAndReset()
 
   def Close(self):
     """Closes this browser."""
@@ skipping 55 matching lines @@
         use_record_mode,
         append_to_existing_wpr,
         self._browser_backend.WEBPAGEREPLAY_HOST,
         self._browser_backend.webpagereplay_local_http_port,
         self._browser_backend.webpagereplay_local_https_port,
         self._browser_backend.webpagereplay_remote_http_port,
         self._browser_backend.webpagereplay_remote_https_port)
 
   def GetStandardOutput(self):
     return self._browser_backend.GetStandardOutput()