Fix clang-format-js to only include repo files

tools/clang-format-js

 #!/bin/bash
 # Copyright 2016 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 if [[ -z "${@}" ]]; then
-  echo >&2 "Usage: `basename $0` <paths_to_clang_format...>";
-  exit 1;
+  echo >&2 "Usage: `basename $0` <paths_to_clang_format...>"
+  exit 1
 fi
 
-which clang-format >/dev/null 2>&1;
+which clang-format >/dev/null 2>&1
 if [[ $? -ne 0 ]]; then
-  echo >&2 "Sorry, but you need \`clang-format\` on your \$PATH to run this script";
-  exit 1;
+  echo >&2 "Sorry, but you need \`clang-format\` on your \$PATH to run this script"
+  exit 1
 fi
 
-for arg in "${@}"; do
+for arg in ${@}; do
+  echo "Processing ${arg}"
+
   dir=`readlink -f "${arg}"`
   if [[ -d "${dir}" ]]; then
     dir="${dir}/stripped-by-dirname-on-next-line"
   fi
   while dir=`dirname ${dir}`; do
     if [[ -f "${dir}/.clang-format" ]]; then
-      echo "Using style from: ${dir}/.clang-format";
-      break;
+      echo "Using style from: ${dir}/.clang-format"
+      break
     elif [[ "${dir}" == "/" ]]; then
-      echo >&2 "No .clang-format file found. Make one at or above ${arg}";
-      exit 1;
+      echo >&2 "No .clang-format file found. Make one at or above ${arg}"
+      exit 1
     fi
   done
+
+  js_files=$(git ls-tree -r --name-only HEAD -- "${arg}" | grep '\.js$')
+
+  for js_file in ${js_files}; do
+    echo "Formatting ${js_file}"
+    clang-format -i -style=file "$js_file"
+  done
 done
-
-find "${@}" -type f -iname '*.js' | xargs clang-format -i -style=file;