[tools/perf] Fix blink_perf tests to find Chrome traces

These tests just want to know whether a Chrome trace has been recorded
or not.

The implementation prior to this CL used to verify whether a serialized
trace.html was recorded after finishing running the story; but this will
no longer be the case after serialization is handed over to results
processor.

Bug: 981349
Change-Id: I39dec39db349cdce6334d950b392fff0d66a001a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1903145
Commit-Queue: Mikhail Khokhlov <khokhlov@google.com>
Auto-Submit: Juan Antonio Navarro Pérez <perezju@chromium.org>
Reviewed-by: Mikhail Khokhlov <khokhlov@google.com>
Cr-Commit-Position: refs/heads/master@{#713478}

tools/perf/benchmarks/blink_perf_unittest.py

@@ -32,6 +32,10 @@ class BlinkPerfTest(legacy_page_test_case.LegacyPageTestCase):
     self.blink_page_test = blink_perf._BlinkPerfMeasurement()
     # pylint: enable=protected-access
 
+  def HasChromeTraces(self):
+    return any(name.startswith('trace/traceEvents/')
+               for name in self.test_result['outputArtifacts'])
+
   @staticmethod
   def CreateStorySetForTest(url):
     story_set = story.StorySet(
@@ -46,7 +50,7 @@ class BlinkPerfTest(legacy_page_test_case.LegacyPageTestCase):
   def testBlinkPerfTracingMetricsForMeasureTime(self):
     measurements = self.RunPageTest(
         self.blink_page_test, 'file://append-child-measure-time.html')
-    self.assertIn('trace.html', self.test_result['outputArtifacts'])
+    self.assertTrue(self.HasChromeTraces())
 
     frame_view_layouts = measurements['LocalFrameView::layout']['samples']
     # append-child-measure-time.html specifies 5 iterationCount.
@@ -61,7 +65,7 @@ class BlinkPerfTest(legacy_page_test_case.LegacyPageTestCase):
   def testBlinkPerfTracingMetricsForMeasureFrameTime(self):
     measurements = self.RunPageTest(
         self.blink_page_test, 'file://color-changes-measure-frame-time.html')
-    self.assertIn('trace.html', self.test_result['outputArtifacts'])
+    self.assertTrue(self.HasChromeTraces())
 
     frame_view_prepaints = measurements[
         'LocalFrameView::RunPrePaintLifecyclePhase']['samples']
@@ -79,7 +83,7 @@ class BlinkPerfTest(legacy_page_test_case.LegacyPageTestCase):
   def testBlinkPerfTracingMetricsForMeasurePageLoadTime(self):
     measurements = self.RunPageTest(
         self.blink_page_test, 'file://simple-html-measure-page-load-time.html')
-    self.assertIn('trace.html', self.test_result['outputArtifacts'])
+    self.assertTrue(self.HasChromeTraces())
 
     create_child_frame = measurements[
         'WebLocalFrameImpl::createChildframe']['samples']
@@ -97,7 +101,7 @@ class BlinkPerfTest(legacy_page_test_case.LegacyPageTestCase):
   def testBlinkPerfTracingMetricsForMeasureAsync(self):
     measurements = self.RunPageTest(
         self.blink_page_test, 'file://simple-blob-measure-async.html')
-    self.assertIn('trace.html', self.test_result['outputArtifacts'])
+    self.assertTrue(self.HasChromeTraces())
 
     blob_requests = measurements['BlobRequest']['samples']
     blob_readers = measurements['BlobReader']['samples']
@@ -124,12 +128,12 @@ class BlinkPerfTest(legacy_page_test_case.LegacyPageTestCase):
 
   def testBlinkPerfLifecycleMethods(self):
     self.RunPageTest(self.blink_page_test, 'file://lifecycle-methods.html')
-    self.assertNotIn('trace.html', self.test_result['outputArtifacts'])
+    self.assertFalse(self.HasChromeTraces())
 
   def testExtraChromeCategories(self):
     self.options.extra_chrome_categories = 'cc,blink'
     self.RunPageTest(self.blink_page_test, 'file://lifecycle-methods.html')
-    self.assertIn('trace.html', self.test_result['outputArtifacts'])
+    self.assertTrue(self.HasChromeTraces())
 
 
 # pylint: disable=protected-access