Fixes for how extension ids are calculated, especially for component extensions.

tools/telemetry/telemetry/core/extension_unittest.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
 import shutil
 import tempfile
 import unittest
 
 from telemetry.core import browser_finder
 from telemetry.core import extension_to_load
@@ skipping 97 matching lines @@
                                self._extensions_to_load)
     self.assertEqual(len(loaded_extensions), len(self._extensions_to_load))
 
     for load_extension in self._extensions_to_load:
       extension = self._browser.extensions[load_extension]
       assert extension
       extension.ExecuteJavaScript('setTestVar("abcdef")')
       self.assertEquals('abcdef', extension.EvaluateJavaScript('_testVar'))
 
 class ComponentExtensionTest(unittest.TestCase):
-  def testComponentExtension(self):
+  def testComponentExtensionBasic(self):
     extension_path = os.path.join(os.path.dirname(__file__),
         '..', '..', 'unittest_data', 'component_extension')
-    load_extension = extension_to_load.ExtensionToLoad(extension_path, False)
+    load_extension = extension_to_load.ExtensionToLoad(extension_path, True)
 
     options = options_for_unittests.GetCopy()
     options.extensions_to_load = [load_extension]
     browser_to_create = browser_finder.FindBrowser(options)
     if not browser_to_create:
       # Some browsers don't support extensions.
       return
 
     with browser_to_create.Create() as b:
       extension = b.extensions[load_extension]
       extension.ExecuteJavaScript('setTestVar("abcdef")')
       self.assertEquals('abcdef', extension.EvaluateJavaScript('_testVar'))
+
+  def testComponentExtensionNoPublicKey(self):
+    # simple_extension does not have a public key.
+    extension_path = os.path.join(os.path.dirname(__file__),
+        '..', '..', 'unittest_data', 'simple_extension')
+    self.assertRaises(extension_to_load.MissingPublicKeyException,
+                      lambda: extension_to_load.ExtensionToLoad(extension_path,
+                                                                True))