Add BenchmarkOptionsTest. Move smoke test to benchmark_smoke_unittest

tools/perf/benchmarks/benchmark_smoke_unittest.py

Index: tools/perf/benchmarks/benchmark_smoke_unittest.py
diff --git a/tools/perf/benchmarks/benchmark_unittest.py b/tools/perf/benchmarks/benchmark_smoke_unittest.py
similarity index 86%
copy from tools/perf/benchmarks/benchmark_unittest.py
copy to tools/perf/benchmarks/benchmark_smoke_unittest.py
index 476804ed536fc00f2d39ba93634411665ec7bc23..fa3532801071a42c5e6a3bc3456a2ca6dd529b7c 100644
--- a/tools/perf/benchmarks/benchmark_unittest.py
+++ b/tools/perf/benchmarks/benchmark_smoke_unittest.py
@@ -2,10 +2,11 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-"""Run the first page of every benchmark that has a composable measurement.
+"""Run the first page of one benchmark for every module.
 
-Ideally this test would be comprehensive, but the above serves as a
-kind of smoke test.
+Only benchmarks that have a composable measurement are included.
+Ideally this test would be comprehensive, however, running one page
+of every benchmark would run impractically long.
 """
 
 import os
@@ -69,11 +70,12 @@ def load_tests(_, _2, _3):
   measurements_dir = os.path.join(top_level_dir, 'measurements')
 
   all_measurements = discover.DiscoverClasses(
-      measurements_dir, top_level_dir, page_test.PageTest,
-      pattern='*.py').values()
+      measurements_dir, top_level_dir, page_test.PageTest).values()
+  # Using the default of |index_by_class_name=False| means that if a module
+  # has multiple benchmarks, only the last one is returned.
   all_benchmarks = discover.DiscoverClasses(
       benchmarks_dir, top_level_dir, benchmark_module.Benchmark,
-      pattern='*.py').values()
+      index_by_class_name=False).values()
   for benchmark in all_benchmarks:
     if benchmark.PageTestClass() not in all_measurements:
       # If the benchmark is not in measurements, then it is not composable.