Proxy only on non standard schemes

Proxying http and https via `convertFileSrc` only works on Android where
the webview runs on custom schemes.

Author: NiklasMerz

src/www/util.js

@@ -2,6 +2,8 @@ var exec = require('cordova/exec');
 
 var WebView = {
   convertFileSrc: function(url) {
+    const convertHttp = !location.protocol.startsWith("http") && !location.protocol.startsWith("https")
+
     if (!url) {
       return url;
     }
@@ -11,10 +13,10 @@ var WebView = {
     if (url.startsWith('file://')) {
       return window.WEBVIEW_SERVER_URL + url.replace('file://', '/_app_file_');
     }
-    if (url.startsWith('http://')) {
+    if (url.startsWith('http://') && convertHttp) {
       return window.WEBVIEW_SERVER_URL + url.replace('http://', '/_http_proxy_');
     }
-    if (url.startsWith('https://')) {
+    if (url.startsWith('https://') && convertHttp) {
       return window.WEBVIEW_SERVER_URL + url.replace('https://', '/_https_proxy_');
     }
     if (url.startsWith('content://')) {