Update reference to page_test module to use legacy_page_test module

content/test/gpu/gpu_tests/trace_test.py

 # Copyright (c) 2015 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.
 from gpu_tests import gpu_test_base
 from gpu_tests import trace_test_expectations
 import page_sets
 
-from telemetry.page import page_test
+from telemetry.page import legacy_page_test
 from telemetry.timeline import model as model_module
 from telemetry.timeline import tracing_config
 
 TOPLEVEL_GL_CATEGORY = 'gpu_toplevel'
 TOPLEVEL_SERVICE_CATEGORY = 'disabled-by-default-gpu.service'
 TOPLEVEL_DEVICE_CATEGORY = 'disabled-by-default-gpu.device'
 TOPLEVEL_CATEGORIES = [TOPLEVEL_SERVICE_CATEGORY, TOPLEVEL_DEVICE_CATEGORY]
 
 test_harness_script = r"""
   var domAutomationController = {};
@@ skipping 34 matching lines @@
     timeline_model = model_module.TimelineModel(timeline_data)
 
     category_name = self.GetCategoryName()
     event_iter = timeline_model.IterAllEvents(
         event_type_predicate=model_module.IsSliceOrAsyncSlice)
     for event in event_iter:
       if (event.args.get('gl_category', None) == TOPLEVEL_GL_CATEGORY and
           event.category == category_name):
         break
     else:
-      raise page_test.Failure(self._FormatException(category_name))
+      raise legacy_page_test.Failure(self._FormatException(category_name))
 
   def CustomizeBrowserOptions(self, options):
     options.AppendExtraBrowserArgs('--enable-logging')
     options.AppendExtraBrowserArgs('--enable-experimental-canvas-features')
 
   def WillNavigateToPage(self, page, tab):
     config = tracing_config.TracingConfig()
     config.chrome_trace_config.category_filter.AddExcludedCategory('*')
     for cat in TOPLEVEL_CATEGORIES:
       config.chrome_trace_config.category_filter.AddDisabledByDefault(
@@ skipping 43 matching lines @@
   """Tests GPU Device traces show up on devices that support it."""
   test = _DeviceTraceValidator
   name = 'DeviceTraceTest'
 
   @classmethod
   def Name(cls):
     return 'device_trace_test'
 
   def _CreateExpectations(self):
     return trace_test_expectations.DeviceTraceTestExpectations()