Add alternate method of parsing to enable orbit benchmarks (#529)

* Add logging lines for debugging purposes

* Add logging.

* Add alternate method of parsing 

Allow for benchmarks to be specified with the format <benchmark_class>:<benchmark_method_name>.

* add logging to check contents of directory.

* Log constructor_args

* Add more logging

* Remove nargs from flag --perfzero_constructor_args

There should only ever be one argument to --perfzero_constructor_args (as all the args are grouped together in a JSON-serialized dict).

* add more constructor arg logging

* Remove extra logging lines.

* Remove extra logging

* Remove logging

Author: brajiang

perfzero/lib/perfzero/benchmark_method_runner.py

@@ -69,9 +69,12 @@ def _run_internal(benchmark_method, harness_info, site_package_info,
   else:
     model_output_dir = output_dir
   utils.make_dir_if_not_exist(output_dir)
-  benchmark_class, benchmark_method_name = benchmark_method.rsplit('.', 1)
+  if ':' in benchmark_method:
+    benchmark_class, benchmark_method_name = benchmark_method.rsplit(':', 1)
+  else:
+    benchmark_class, benchmark_method_name = benchmark_method.rsplit('.', 1)
   benchmark_class_name = benchmark_class.rsplit('.', 1)[1]
-
+        
   tensorflow_profiler = TensorFlowProfiler(
       config.profiler_enabled_time_str, output_dir)
   process_info_tracker = ProcessInfoTracker(output_dir)