Add an "in_unit_test_mode" attribute to the environment. Use this to default output format to 'gtes…

content/test/gpu/gpu_tests/memory.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 memory_expectations
 import page_sets
 
 from telemetry import benchmark
 from telemetry.page import page_test
 from telemetry.timeline import counter
 from telemetry.timeline import model
@@ skipping 45 matching lines @@
   }
 
   window.domAutomationController = domAutomationController;
 
   window.addEventListener("load", function() {
     useGpuMemory(%d);
   }, false);
 """ % MEMORY_LIMIT_MB
 
 class _MemoryValidator(page_test.PageTest):
+  options = {'output_format': 'gtest'}
+
   def ValidatePage(self, page, tab, results):
     timeline_data = tab.browser.StopTracing()
     timeline_model = model.TimelineModel(timeline_data)
     for process in timeline_model.GetAllProcesses():
       if 'gpu.GpuMemoryUsage' in process.counters:
         counter = process.GetCounter('gpu', 'GpuMemoryUsage')
         mb_used = counter.samples[-1] / 1048576
 
     if mb_used + WIGGLE_ROOM_MB < SINGLE_TAB_LIMIT_MB:
       raise page_test.Failure(self._FormatException('low', mb_used))
@@ skipping 22 matching lines @@
   page_set = page_sets.MemoryTestsPageSet
 
   def CreateExpectations(self, page_set):
     return memory_expectations.MemoryExpectations()
 
   def CreatePageSet(self, options):
     page_set = super(Memory, self).CreatePageSet(options)
     for page in page_set.pages:
       page.script_to_evaluate_on_commit = test_harness_script
     return page_set