[Telemetry] Reduce misleading spam in unittest output.

tools/telemetry/telemetry/page/page_runner.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 collections
 import copy
 import logging
 import optparse
 import os
 import random
@@ skipping 486 matching lines @@
   if expectation == 'skip':
     logging.debug('Skipping test: Skip expectation for %s', page.url)
     results.AddSkip(page, 'Skipped by test expectations')
     return
 
   logging.info('Running %s', page.url)
 
   page_state = PageState(page, test.TabForPage(page, state.browser))
 
   def ProcessError():
-    logging.error('%s:', page.url)
-    exception_formatter.PrintFormattedException()
     if expectation == 'fail':
-      logging.info('Error was expected\n')
+      msg = 'Expected exception while running %s' % page.url
       results.AddSuccess(page)
     else:
+      msg = 'Exception while running %s' % page.url
       results.AddError(page, sys.exc_info())
+    exception_formatter.PrintFormattedException(msg=msg)
 
   try:
     page_state.PreparePage(test)
     if state.repeat_state.ShouldNavigate(
         finder_options.skip_navigate_on_repeat):
       page_state.ImplicitPageNavigation(test)
     test.RunPage(page, page_state.tab, results)
     util.CloseConnections(page_state.tab)
   except page_test.TestNotSupportedOnPlatformFailure:
     raise
   except page_test.Failure:
     if expectation == 'fail':
-      logging.info('%s:', page.url)
-      exception_formatter.PrintFormattedException()
-      logging.info('Failure was expected\n')
+      exception_formatter.PrintFormattedException(
+          msg='Expected failure while running %s' % page.url)
       results.AddSuccess(page)
     else:
-      logging.warning('%s:', page.url)
-      exception_formatter.PrintFormattedException()
+      exception_formatter.PrintFormattedException(
+          msg='Failure while running %s' % page.url)
       results.AddFailure(page, sys.exc_info())
   except (util.TimeoutException, exceptions.LoginException,
           exceptions.ProfilingException):
     ProcessError()
   except (exceptions.TabCrashException, exceptions.BrowserGoneException):
     ProcessError()
     # Run() catches these exceptions to relaunch the tab/browser, so re-raise.
     raise
   except page_action.PageActionNotSupported as e:
     results.AddSkip(page, 'Unsupported page action: %s' % e)
   except Exception:
-    logging.warning('While running %s', page.url)
-    exception_formatter.PrintFormattedException()
+    exception_formatter.PrintFormattedException(
+        msg='Unhandled exception while running %s' % page.url)
     results.AddFailure(page, sys.exc_info())
   else:
     if expectation == 'fail':
       logging.warning('%s was expected to fail, but passed.\n', page.url)
     results.AddSuccess(page)
   finally:
     page_state.CleanUpPage(test)
 
 
 def _WaitForThermalThrottlingIfNeeded(platform):
@@ skipping 11 matching lines @@
     logging.warning('Device is thermally throttled before running '
                     'performance tests, results will vary.')
 
 
 def _CheckThermalThrottling(platform):
   if not platform.CanMonitorThermalThrottling():
     return
   if platform.HasBeenThermallyThrottled():
     logging.warning('Device has been thermally throttled during '
                     'performance tests, results will vary.')