Telemetry support for extensions.

tools/telemetry/telemetry/possible_browser.py

Index: tools/telemetry/telemetry/possible_browser.py
===================================================================
--- tools/telemetry/telemetry/possible_browser.py	(revision 178380)
+++ tools/telemetry/telemetry/possible_browser.py	(working copy)
@@ -7,9 +7,10 @@
   Call Create() to launch the browser and begin manipulating it..
   """
 
-  def __init__(self, browser_type, options):
+  def __init__(self, browser_type, options, supports_extensions):
     self.browser_type = browser_type
     self._options = options
+    self._supports_extensions = supports_extensions
 
   def __repr__(self):
     return 'PossibleBrowser(browser_type=%s)' % self.browser_type
@@ -18,5 +19,9 @@
   def options(self):
     return self._options
 
+  @property
+  def supports_extensions(self):
+    return self._supports_extensions
+
   def Create(self):
     raise NotImplementedError()