--- a/testing/marionette/harness/marionette_harness/tests/unit/test_crash.py
+++ b/testing/marionette/harness/marionette_harness/tests/unit/test_crash.py
@@ -26,17 +26,17 @@ class MockMozCrash(object):
                   return true;
                 } catch (exc) {
                   return false;
                 }
             """)
 
     def check_for_crashes(self, dump_directory, *args, **kwargs):
         minidump_files = glob.glob('{}/*.dmp'.format(dump_directory))
-        shutil.rmtree(dump_directory, ignore_errors=True)
+        shutil.rmtree(dump_directory)
 
         if self.crash_reporter_enabled:
             return len(minidump_files)
         else:
             return len(minidump_files) == 0
 
     def log_crashes(self, logger, dump_directory, *args, **kwargs):
         return self.check_for_crashes(dump_directory, *args, **kwargs)
@@ -45,73 +45,71 @@ class MockMozCrash(object):
 class BaseCrashTestCase(MarionetteTestCase):
 
     # Reduce the timeout for faster processing of the tests
     socket_timeout = 10
 
     def setUp(self):
         super(BaseCrashTestCase, self).setUp()
 
-        self.mozcrash_mock = MockMozCrash(self.marionette)
+        # Monkey patch mozcrash to avoid crash info output only for our triggered crashes.
+        self.mozcrash = runner.mozcrash
+        runner.mozcrash = MockMozCrash(self.marionette)
+
         self.crash_count = self.marionette.crashed
         self.pid = self.marionette.process_id
         self.remote_uri = self.marionette.absolute_url("javascriptPage.html")
 
     def tearDown(self):
+        # Replace mockup with original mozcrash instance
+        runner.mozcrash = self.mozcrash
+
         self.marionette.crashed = self.crash_count
 
         super(BaseCrashTestCase, self).tearDown()
 
     def crash(self, chrome=True):
         context = 'chrome' if chrome else 'content'
         sandbox = None if chrome else 'system'
 
-        # Monkey patch mozcrash to avoid crash info output only for our triggered crashes.
-        mozcrash = runner.mozcrash
-        runner.mozcrash = self.mozcrash_mock
-
         socket_timeout = self.marionette.client.socket_timeout
+        self.marionette.client.socket_timeout = self.socket_timeout
 
         self.marionette.set_context(context)
         try:
-            self.marionette.client.socket_timeout = self.socket_timeout
             self.marionette.execute_script("""
               // Copied from crash me simple
               Components.utils.import("resource://gre/modules/ctypes.jsm");
 
               // ctypes checks for NULL pointer derefs, so just go near-NULL.
               var zero = new ctypes.intptr_t(8);
               var badptr = ctypes.cast(zero, ctypes.PointerType(ctypes.int32_t));
               var crash = badptr.contents;
             """, sandbox=sandbox)
         finally:
-            runner.mozcrash = mozcrash
             self.marionette.client.socket_timeout = socket_timeout
 
 
 class TestCrash(BaseCrashTestCase):
 
     def test_crash_chrome_process(self):
         self.assertRaisesRegexp(IOError, 'Process crashed',
                                 self.crash, chrome=True)
         self.assertEqual(self.marionette.crashed, 1)
         self.assertIsNone(self.marionette.session)
         self.assertRaisesRegexp(MarionetteException, 'Please start a session',
                                 self.marionette.get_url)
 
         self.marionette.start_session()
         self.assertNotEqual(self.marionette.process_id, self.pid)
 
-        # TODO: Bug 1314594 - Causes a hang for the communication between the
-        # chrome and frame script.
-        # self.marionette.get_url()
+        self.marionette.get_url()
 
     @run_if_e10s("Content crashes only exist in e10s mode")
     def test_crash_content_process(self):
-        # If e10s is disabled the chrome process crashes
         self.marionette.navigate(self.remote_uri)
 
         self.assertRaisesRegexp(IOError, 'Content process crashed',
                                 self.crash, chrome=False)
         self.assertEqual(self.marionette.crashed, 1)
         self.assertIsNone(self.marionette.session)
         self.assertRaisesRegexp(MarionetteException, 'Please start a session',
                                 self.marionette.get_url)