Update reference to page_test module to use legacy_page_test module

content/test/gpu/gpu_tests/gpu_process.py

Index: content/test/gpu/gpu_tests/gpu_process.py
diff --git a/content/test/gpu/gpu_tests/gpu_process.py b/content/test/gpu/gpu_tests/gpu_process.py
index ac47083ab41bf6f2cf3a9824f0b62e30df6e5920..187b6b7ee116b61674154cf6fdbdb3a8f8ba37fb 100644
--- a/content/test/gpu/gpu_tests/gpu_process.py
+++ b/content/test/gpu/gpu_tests/gpu_process.py
@@ -5,7 +5,7 @@ from gpu_tests import gpu_process_expectations as expectations
 from gpu_tests import gpu_test_base
 import page_sets
 
-from telemetry.page import page_test
+from telemetry.page import legacy_page_test
 
 test_harness_script = r"""
   var domAutomationController = {};
@@ -41,7 +41,7 @@ class GpuProcessValidator(gpu_test_base.ValidatorBase):
       has_gpu_channel_js = 'chrome.gpuBenchmarking.hasGpuChannel()'
       has_gpu_channel = tab.EvaluateJavaScript(has_gpu_channel_js)
       if not has_gpu_channel:
-        raise page_test.Failure('No GPU channel detected')
+        raise legacy_page_test.Failure('No GPU channel detected')
 
 class GpuProcess(gpu_test_base.TestBase):
   """Tests that accelerated content triggers the creation of a GPU process"""