telemetry: Remove command line args from page test

tools/perf/measurements/screenshot.py

Index: tools/perf/measurements/screenshot.py
diff --git a/tools/perf/measurements/screenshot.py b/tools/perf/measurements/screenshot.py
index e3b0c3379e3c27912ad433eaa246549875b2ea84..196e3d84a386765f463e9dd53caf554d61df9284 100644
--- a/tools/perf/measurements/screenshot.py
+++ b/tools/perf/measurements/screenshot.py
@@ -9,21 +9,11 @@ from telemetry.value import scalar
 
 
 class Screenshot(page_test.PageTest):
-  def __init__(self):
+  def __init__(self, png_outdir):
     super(Screenshot, self).__init__(
         action_name_to_run = 'RunPrepareForScreenshot',
         is_action_name_to_run_optional=True)
-
-  @classmethod
-  def AddCommandLineArgs(cls, parser):
-    parser.add_option('--png-outdir',
-                      help='Output directory for the PNG files')
-
-  @classmethod
-  def ProcessCommandLineArgs(cls, parser, args):
-    if not args.png_outdir:
-      parser.error('Please specify --png-outdir')
-    cls._png_outdir = args.png_outdir
+    self._png_outdir = png_outdir
 
   def ValidateAndMeasurePage(self, page, tab, results):
     if not tab.screenshot_supported: