[web tests] Move look up of physical and virtual test suite args outside of loop

These operations don't depend on the reference files, therefore we don't need to
look for these args for each reference file.

Bug: chromium:982208
Change-Id: Ie3ffe4491d3ff5f23ccc087b60e6bb969c02bfa2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1817774Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Commit-Queue: Rakib Hasan <rmhasan@google.com>
Cr-Commit-Position: refs/heads/master@{#699073}

third_party/blink/tools/blinkpy/web_tests/controllers/single_test_runner.py

@@ -512,11 +512,11 @@ class SingleTestRunner(object):
         test_result = None
         putAllMismatchBeforeMatch = sorted
         reference_test_names = []
+        if self._port.lookup_virtual_test_base(self._test_name):
+            args = self._port.lookup_virtual_reference_args(self._test_name)
+        else:
+            args = self._port.lookup_physical_reference_args(self._test_name)
         for expectation, reference_filename in putAllMismatchBeforeMatch(self._reference_files):
-            if self._port.lookup_virtual_test_base(self._test_name):
-                args = self._port.lookup_virtual_reference_args(self._test_name)
-            else:
-                args = self._port.lookup_physical_reference_args(self._test_name)
             reference_test_name = self._port.relative_test_filename(reference_filename)
             reference_test_names.append(reference_test_name)
             driver_input = DriverInput(reference_test_name, self._timeout_ms,