fix(ios): Entry.toURL() to produce DOM-usable uri when using scheme-hosted webview

plugin.xml

@@ -182,6 +182,9 @@ to config.xml in order for the application to find previously stored files.
         <source-file src="src/ios/CDVAssetLibraryFilesystem.m" />
 
         <!-- ios specific file apis -->
+        <js-module src="www/ios/Entry.js" name="iosEntry">
+            <merges target="Entry" />
+        </js-module>
         <js-module src="www/ios/FileSystem.js" name="iosFileSystem">
             <merges target="FileSystem" />
         </js-module>

www/ios/Entry.js

@@ -0,0 +1,33 @@
+/*
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ *
+*/
+
+module.exports = {
+    /**
+   * Return a URL that can be used to identify this entry.
+   * Use a URL that can be used to as the src attribute of a <video> or
+   * <audio> tag. If that is not possible, construct a http(s)://(localhost) URL.
+   */
+    toURL: function () {
+        return window.location.origin.includes('file://')
+            ? this.nativeURL
+            : window.WkWebView.convertFilePath(this.nativeURL);
+    }
+};