MD Settings: Remove some ES6 leftovers from CrOS code that break uglify.

chrome/browser/resources/settings/languages_page/manage_input_methods_page.js

Index: chrome/browser/resources/settings/languages_page/manage_input_methods_page.js
diff --git a/chrome/browser/resources/settings/languages_page/manage_input_methods_page.js b/chrome/browser/resources/settings/languages_page/manage_input_methods_page.js
index ad3690d965096009df1c96c688e97e2d0b95867b..92d122370a5e1e48c5d41e155a2838ea820e4e40 100644
--- a/chrome/browser/resources/settings/languages_page/manage_input_methods_page.js
+++ b/chrome/browser/resources/settings/languages_page/manage_input_methods_page.js
@@ -144,8 +144,8 @@ Polymer({
         language: displayLanguage,
         inputMethods: combinedInputMethods,
       });
-      for (var languageCode of languageFamilyCodes)
-        usedLanguages.add(languageCode);
+      for (var k = 0; k < languageFamilyCodes.length; k++)
+        usedLanguages.add(languageFamilyCodes[k]);
     }
 
     this.languageList_ = languageList;
@@ -163,9 +163,9 @@ Polymer({
     var /** !Set<string> */ usedInputMethods = new Set();
     /** @type {!Array<chrome.languageSettingsPrivate.InputMethod>} */
     var combinedInputMethods = [];
-    for (var languageCode of languageCodes) {
+    for (var i = 0; i < languageCodes.length; i++) {
       var inputMethods = this.languageHelper.getInputMethodsForLanguage(
-          languageCode);
+          languageCodes[i]);
       // Get the language's unused input methods and mark them as used.
       var newInputMethods = inputMethods.filter(function(inputMethod) {
         if (usedInputMethods.has(inputMethod.id))