Extension profile generator + benchmark for startup with profile.

tools/perf/profile_creators/profile_extender.py

 # Copyright 2013 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.
 
 from telemetry.core import platform
 from telemetry.util import wpr_modes
 from telemetry.internal.browser import browser_finder
 from telemetry.internal.browser import browser_finder_exceptions
 
 
@@ skipping 40 matching lines @@
 
   @property
   def profile_path(self):
     """The path of the profile that the browser will use while it's running."""
     return self.finder_options.output_profile_path
 
   @property
   def browser(self):
     return self._browser
 
+  def EnabledOSList(self):
+    """Returns a list of OSes that this extender can run on.
+
+    Can be overridden by subclasses.
+
+    Returns:
+        List of OS ('win', 'mac', or 'linux') that this extender can run on.
+        None if this extender can run on all platforms.
+    """
+    return None
+
   def SetUpBrowser(self):
     """Finds and starts the browser.
 
     Can be overridden by subclasses. The subclass implementation must call the
     super class implementation.
 
     Subclasses do not need to call this method. This method is only necessary
     if the subclass needs to start a browser. If a subclass does call this
     method, the subclass must also call TearDownBrowser().
     """
     possible_browser = self._GetPossibleBrowser(self.finder_options)
 
+    os_name = possible_browser.platform.GetOSName()
+    enabled_os_list = self.EnabledOSList()
+    if enabled_os_list is not None and os_name not in enabled_os_list:
+      raise NotImplementedError(
+        'This profile extender on %s is not yet supported'
+        % os_name)
+
     assert possible_browser.supports_tab_control
     assert (platform.GetHostPlatform().GetOSName() in
         ["win", "mac", "linux"])
 
     self._SetUpWebPageReplay(self.finder_options, possible_browser)
     self._browser = possible_browser.Create(self.finder_options)
 
   def TearDownBrowser(self):
     """Tears down the browser.
 
@@ skipping 40 matching lines @@
     possible_browser = browser_finder.FindBrowser(finder_options)
     if not possible_browser:
       raise browser_finder_exceptions.BrowserFinderException(
           'No browser found.\n\nAvailable browsers:\n%s\n' %
           '\n'.join(browser_finder.GetAllAvailableBrowserTypes(finder_options)))
     finder_options.browser_options.browser_type = (
         possible_browser.browser_type)
 
     return possible_browser