MD Settings: Eliminate use of ES6 for Chrome OS

chrome/browser/resources/settings/internet_page/network_proxy.js

Index: chrome/browser/resources/settings/internet_page/network_proxy.js
diff --git a/chrome/browser/resources/settings/internet_page/network_proxy.js b/chrome/browser/resources/settings/internet_page/network_proxy.js
index 01a2a083aa86c49d0377a5ceafb262fe7df20f1b..d5b65df0e4997265e7bca95cd98d10b95056b6ca 100644
--- a/chrome/browser/resources/settings/internet_page/network_proxy.js
+++ b/chrome/browser/resources/settings/internet_page/network_proxy.js
@@ -153,7 +153,7 @@ Polymer({
     // For shared networks with unmanaged proxy settings, ignore any saved
     // proxy settings (use the default values).
     if (this.isShared_()) {
-      let property = this.getProxySettingsTypeProperty_();
+      var property = this.getProxySettingsTypeProperty_();
       if (!this.isControlled(property) && !this.useSharedProxies_) {
         this.setProxyAsync_(proxy);
         return;  // Proxy settings will be ignored.
@@ -184,11 +184,11 @@ Polymer({
             /** @type {!CrOnc.ProxyLocation|undefined} */ (
                 CrOnc.getSimpleActiveProperties(proxySettings.Manual.SOCKS)) ||
             proxy.Manual.HTTPProxy;
-        let json_http = JSON.stringify(proxy.Manual.HTTPProxy);
+        var jsonHttp = JSON.stringify(proxy.Manual.HTTPProxy);
         this.useSameProxy_ =
-            json_http == JSON.stringify(proxy.Manual.SecureHTTPProxy) &&
-            json_http == JSON.stringify(proxy.Manual.FTPProxy) &&
-            json_http == JSON.stringify(proxy.Manual.SOCKS);
+            jsonHttp == JSON.stringify(proxy.Manual.SecureHTTPProxy) &&

[dpapad, 2017/01/23 19:12:54]

FWIW: There are no guarantees that JSON.stringify() serializes properties in a
deterministic order, so comparisons like this are a bit fragile.

From the documenatation, "Properties of non-array objects are not guaranteed to
be stringified in any particular order", see
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Obje....

[stevenjb, 2017/01/24 02:02:04]

I'm pretty sure that in this context JSON.stringify will be consistent, but it's
not exactly optimal anyway; done.

+            jsonHttp == JSON.stringify(proxy.Manual.FTPProxy) &&
+            jsonHttp == JSON.stringify(proxy.Manual.SOCKS);
       }
       if (proxySettings.ExcludeDomains) {
         proxy.ExcludeDomains = /** @type {!Array<string>|undefined} */ (
@@ -228,7 +228,7 @@ Polymer({
 
   /** @private */
   useSharedProxiesChanged_: function() {
-    let pref = this.getPref('settings.use_shared_proxies');
+    var pref = this.getPref('settings.use_shared_proxies');
     this.useSharedProxies_ = !!pref && !!pref.value;
     this.updateProxy_();
   },
@@ -257,10 +257,10 @@ Polymer({
    */
   sendProxyChange_: function() {
     if (this.proxy_.Type == CrOnc.ProxySettingsType.MANUAL) {
-      let proxy =
+      var proxy =
           /** @type {!CrOnc.ProxySettings} */ (Object.assign({}, this.proxy_));
-      let manual = proxy.Manual;
-      let defaultProxy = manual.HTTPProxy;
+      var manual = proxy.Manual;
+      var defaultProxy = manual.HTTPProxy;
       if (!defaultProxy || !defaultProxy.Host)
         return;
       if (this.useSameProxy_ || !this.get('SecureHTTPProxy.Host', manual)) {
@@ -292,7 +292,7 @@ Polymer({
    * @private
    */
   onTypeChange_: function(event) {
-    let target = /** @type {!HTMLSelectElement} */ (event.target);
+    var target = /** @type {!HTMLSelectElement} */ (event.target);
     var type = /** @type {chrome.networkingPrivate.ProxySettingsType} */ (
         target.value);
     this.set('proxy_.Type', type);
@@ -370,7 +370,7 @@ Polymer({
    * @private
    */
   shouldShowNetworkPolicyIndicator_: function() {
-    let property = this.getProxySettingsTypeProperty_();
+    var property = this.getProxySettingsTypeProperty_();
     return !!property && !this.isExtensionControlled(property) &&
         this.isNetworkPolicyEnforced(property);
   },
@@ -380,7 +380,7 @@ Polymer({
    * @private
    */
   shouldShowExtensionIndicator_: function() {
-    let property = this.getProxySettingsTypeProperty_();
+    var property = this.getProxySettingsTypeProperty_();
     return !!property && this.isExtensionControlled(property);
   },
 
@@ -403,7 +403,7 @@ Polymer({
       return false;
     if (!this.networkProperties.hasOwnProperty('ProxySettings'))
       return true;  // No proxy settings defined, so not enforced.
-    let property = /** @type {!CrOnc.ManagedProperty|undefined} */ (
+    var property = /** @type {!CrOnc.ManagedProperty|undefined} */ (
         this.get('ProxySettings.' + propertyName, this.networkProperties));
     if (!property)
       return true;