Refactory code.

core/js/get_focus_text.js

@@ -1,17 +1,20 @@
 (function() {
     const activeElement = document.activeElement;
     var inputs = ["input", "select", "textarea"];
+    var pageUrl = window.location.href;
+    var tagName = activeElement.tagName.toLowerCase();
 
-    if (window.location.href === "https://mail.qq.com/" && activeElement) {
+    if (pageUrl === "https://mail.qq.com/" && activeElement) {
         // QQ mail have some security mechanism that we can't fetch value of activeElement.
         // So we just return empty string make is_focus method works well in browser.py
         return "";
-    } else if (activeElement && inputs.indexOf(activeElement.tagName.toLowerCase()) !== -1) {
+    } else if (activeElement && inputs.indexOf(tagName) !== -1) {
         return activeElement.value;
     } else {
-        if (window.location.href.startsWith("https://web.telegram.org/") && activeElement.hasAttribute("placeholder")) {
+        if (pageUrl.startsWith("https://web.telegram.org/") && activeElement.hasAttribute("placeholder")) {
             return activeElement.textContent;
-        } else if ((window.location.href.startsWith("https://console.cloud.google.com/") || window.location.href.startsWith("https://ssh.cloud.google.com/")) && activeElement.tagName.toLowerCase() == "iframe") {
+        } else if ((pageUrl.startsWith("https://console.cloud.google.com/") || pageUrl.startsWith("https://ssh.cloud.google.com/")) && tagName == "iframe") {
+            // Make user can type text in Terminal of Google Cloud.
             return "";
         } else {
             return undefined;