DevTools: In l10n presubmit, apply ignore list to modified files

Change-Id: I31caa742e32727fcdd3c992fca0f815fefbf9740
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1818609
Auto-Submit: Paul Irish <paulirish@chromium.org>
Reviewed-by: Mandy Chen <mandy.chen@microsoft.com>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Yang Guo <yangguo@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#699714}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: ea03feb17d2dac76b800aa9dd586a1812527bc2c
diff --git a/scripts/check_localizability.js b/scripts/check_localizability.js
index 98e695c..a001b19 100644
--- a/scripts/check_localizability.js
+++ b/scripts/check_localizability.js
@@ -46,7 +46,7 @@
     if (process.argv[2] === '-a')
       filePathPromises.push(localizationUtils.getFilesFromDirectory(frontendPath, filePaths, ['.js']));
     else
-      filePaths = process.argv.slice(2);
+      filePaths = process.argv.slice(2).filter(localizationUtils.shouldParseDirectory);
     await Promise.all(filePathPromises);
 
     filePaths.push(localizationUtils.SHARED_STRINGS_PATH);