[test] Roll out new test runner to all testing with arch x64

This will affect all manual test runs with x64. Most bots on x64 already
migrated.

TBR=sergiyb@chromium.org
NOTRY=true

Bug: v8:7343
Change-Id: I87f46f1848a813c0b320b3e9901481b9232025a5
Reviewed-on: https://chromium-review.googlesource.com/883101
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50825}

tools/testrunner/standard_runner.py

@@ -106,7 +106,7 @@ _RE_TYPE = type(re.compile(''))
 # Specifies which architectures are whitelisted to use the staging test-runner.
 # List of arch strings, e.g. "x64".
 ARCH_WHITELIST_STAGING = [
-
+  'x64',
 ]
 
 class StandardTestRunner(base_runner.BaseTestRunner):

tools/unittests/run_tests_test.py

@@ -101,6 +101,8 @@ def run_tests(basedir, *args, **kwargs):
     sys_args = ['--command-prefix', sys.executable] + list(args)
     if kwargs.get('infra_staging', False):
       sys_args.append('--infra-staging')
+    else:
+      sys_args.append('--no-infra-staging')
     code = standard_runner.StandardTestRunner(
         basedir=basedir).execute(sys_args)
     return Result(stdout.getvalue(), stderr.getvalue(), code)