Presubmit: Limit number of files in JS style check

On very large CLs, it's possible that we can run into the same windows
command line length issues for the _CheckDevToolsStyleJS as _CheckDevToolsStyleCSS.

This CL imposes the same 50 file limit as the CSS style check.

Bug: 1198243
Change-Id: I84561dcd37c88c00ceb141cfc21adc050a9544cf
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/2821307
Commit-Queue: Brandon Goddard <brgoddar@microsoft.com>
Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Reviewed-by: Jack Franklin <jacktfranklin@chromium.org>
diff --git a/PRESUBMIT.py b/PRESUBMIT.py
index 5f83483..0f26c2c 100644
--- a/PRESUBMIT.py
+++ b/PRESUBMIT.py
@@ -246,6 +246,11 @@
     if should_bail_out:
         return results
 
+    # If there are more than 50 files to check, don't bother and check
+    # everything, so as to not run into command line length limits on Windows.
+    if len(files_to_lint) > 50:
+        files_to_lint = []
+
     results.extend(
         _checkWithNodeScript(input_api, output_api, lint_path, files_to_lint))
     return results