nvda_chrome_tests.py should not block on speech during setup.

The setup of these tests should not be testing for speech. Instead
if speech doesn't work, the test cases will catch it.

Bug: 742592
Change-Id: I656a40ae8a304ac1161941929d88409aacc144ae
Reviewed-on: https://chromium-review.googlesource.com/599590
Commit-Queue: Doug Turner <dougt@chromium.org>
Reviewed-by: Alice Boxhall <aboxhall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#491903}

tools/accessibility/nvda/nvda_chrome_tests.py

@@ -117,11 +117,6 @@ class NvdaChromeTest(unittest.TestCase):
     self._pywinauto_window = app.top_window_()
     self.last_nvda_log_line = 0;
 
-    try:
-      self._TestForSpeech(['Address and search bar edit', 'about:blank'])
-    except:
-      self.tearDown()
-
   def tearDown(self):
     print()
     print('Shutting down')