[Telemetry] Explicitly define Name() method for all perf benchmarks

tools/perf/benchmarks/indexeddb_perf.py

Index: tools/perf/benchmarks/indexeddb_perf.py
diff --git a/tools/perf/benchmarks/indexeddb_perf.py b/tools/perf/benchmarks/indexeddb_perf.py
index e79c2ffcbb3d7d81c9fb76f1910639b1cf7590a3..031a92c6ab92cabc216fbcce56d4ac65ac02e6b8 100644
--- a/tools/perf/benchmarks/indexeddb_perf.py
+++ b/tools/perf/benchmarks/indexeddb_perf.py
@@ -96,6 +96,10 @@ class IndexedDb(benchmark.Benchmark):
   """Chromium's IndexedDB Performance tests."""
   test = _IndexedDbMeasurement
 
+  @classmethod
+  def Name(cls):
+    return 'indexeddb_perf'
+
   def CreatePageSet(self, options):
     indexeddb_dir = os.path.join(util.GetChromiumSrcDir(), 'chrome', 'test',
                                  'data', 'indexeddb')