Reland of [testing/script] Switch run_telemetry_as_googletest.py to produce...

Reland of [testing/script] Switch run_telemetry_as_googletest.py to produce full json results format (patchset #1 id:1 of https://codereview.chromium.org/2408043002/ )

Reason for revert:
Mac 10.10 Tests & Mac 10.11 Tests are now swarmed:
https://uberchromegw.corp.google.com/i/chromium.mac/builders/Mac10.10%20Tests/builds/8831

https://uberchromegw.corp.google.com/i/chromium.mac/builders/Mac10.11%20Tests/builds/3344

Original issue's description:
> Revert of [testing/script] Switch run_telemetry_as_googletest.py to produce full json results format (patchset #2 id:20001 of https://codereview.chromium.org/2403913002/ )
>
> Reason for revert:
> Speculatively reverting this patch (suggested by findit) to see if it fixes Mac telemetry unit tests.
>
> https://uberchromegw.corp.google.com/i/chromium.mac/builders/Mac10.10%20Tests/builds/8276
>
> https://uberchromegw.corp.google.com/i/chromium.mac/builders/Mac10.10%20Tests/builds/8277
>
> Original issue's description:
> > [testing/script] Switch run_telemetry_as_googletest.py to produce full json results format
> >
> > BUG=649762
> >
> > Committed: https://crrev.com/caa3b797728c9337fcea7d108a087d005fa7f451
> > Cr-Commit-Position: refs/heads/master@{#424206}
>
> TBR=kbr@chromium.org,dpranke@chromium.org,nednguyen@google.com
> # Skipping CQ checks because original CL landed less than 1 days ago.
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
> BUG=649762
>
> Committed: https://crrev.com/12b54d66ba1ce9e7a6c729fdf136b5b5c257b6f2
> Cr-Commit-Position: refs/heads/master@{#424341}

TBR=kbr@chromium.org,dpranke@chromium.org,loyso@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=649762

Review-Url: https://codereview.chromium.org/2480273002
Cr-Commit-Position: refs/heads/master@{#430285}

testing/scripts/run_telemetry_as_googletest.py

@@ -35,7 +35,7 @@ import xvfb
 def main():
   parser = argparse.ArgumentParser()
   parser.add_argument(
-      '--isolated-script-test-output', type=argparse.FileType('w'),
+      '--isolated-script-test-output', type=str,
       required=True)
   parser.add_argument('--xvfb', help='Start xvfb.', action='store_true')
   args, rest_args = parser.parse_known_args()
@@ -72,23 +72,8 @@ def main():
       '--shard-index=%d' % shard_index
     ]
   try:
-    with common.temporary_file() as tempfile_path:
-      rc = common.run_command([sys.executable] + rest_args + sharding_args + [
-        '--write-full-results-to', tempfile_path,
-      ], env=env)
-      with open(tempfile_path) as f:
-        results = json.load(f)
-      parsed_results = common.parse_common_test_results(results,
-                                                        test_separator='.')
-      failures = parsed_results['unexpected_failures']
-
-      json.dump({
-          'valid': bool(rc <= common.MAX_FAILURES_EXIT_STATUS and
-                        ((rc == 0) or failures)),
-          'failures': failures.keys(),
-      }, args.isolated_script_test_output)
-
-    return rc
+    return common.run_command([sys.executable] + rest_args + sharding_args + [
+      '--write-full-results-to', args.isolated_script_test_output], env=env)
   finally:
     xvfb.kill(xvfb_proc)
     xvfb.kill(openbox_proc)