Explicitly setting story names for the dromaeo story sets.

BUG=chromium:720002

Review-Url: https://codereview.chromium.org/2914733002
Cr-Commit-Position: refs/heads/master@{#476143}

tools/perf/benchmarks/dromaeo.py

@@ -118,10 +118,11 @@ class _DromaeoBenchmark(perf_benchmark.PerfBenchmark):
     ps = story.StorySet(
         archive_data_file=archive_data_file,
         base_dir=os.path.dirname(os.path.abspath(__file__)),
-        cloud_storage_bucket=story.PUBLIC_BUCKET)
+        cloud_storage_bucket=story.PUBLIC_BUCKET,
+        verify_names=True)
     url = 'http://dromaeo.com?%s' % self.query_param
     ps.AddStory(page_module.Page(
-        url, ps, ps.base_dir, make_javascript_deterministic=False))
+        url, ps, ps.base_dir, make_javascript_deterministic=False, name=url))
     return ps