JS Modulizer: Handle files with non-ascii characters

This is needed to autogenerate a JS module version of
chrome/test/data/webui/settings/fake_language_settings_private.js

Bug: 1026426
Change-Id: I5b3886cde240494235dda367f43af1d0e90a3085
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2076556Reviewed-by: Demetrios Papadopoulos <dpapad@chromium.org>
Commit-Queue: Rebekah Potter <rbpotter@chromium.org>
Cr-Commit-Position: refs/heads/master@{#745218}

ui/webui/resources/tools/js_modulizer.py

@@ -68,8 +68,8 @@ def ProcessFile(filename, out_folder, namespace_rewrites):
   indices_to_remove = [];
   renames = {}
 
-  with open(filename) as f:
-    lines = f.readlines()
+  with io.open(filename, encoding='utf-8', mode='r') as f:
+    lines = f.readlines();
     ignore_remaining_lines = False
     cr_define_start_index = -1
     cr_define_end_index = -1

ui/webui/resources/tools/js_modulizer_test.py

@@ -56,5 +56,9 @@ class JsModulizerTest(unittest.TestCase):
   def testSuccess_WithIgnore(self):
     self._run_test_('with_ignore.js', 'with_ignore_expected.js')
 
+  def testSuccess_NonAscii(self):
+    self._run_test_('non_ascii.js', 'non_ascii_expected.js')
+
+
 if __name__ == '__main__':
   unittest.main()

ui/webui/resources/tools/tests/non_ascii.js

+/* #export */ function asciiLanguageName() {
+  return 'English';
+}
+/* #export */ function nonAsciiLanguageName() {
+  return 'Ελληνικά';
+}
+function baz() {}

ui/webui/resources/tools/tests/non_ascii_expected.js

+export function asciiLanguageName() {
+  return 'English';
+}
+export function nonAsciiLanguageName() {
+  return 'Ελληνικά';
+}
+function baz() {}