[Android Webview] Refactor LoadUrlTest and work on embedded_test_server custom handler

android_webview/embeddedtestserver/java/src/org/chromium/net/test/IAwEmbeddedTestServerImpl.aidl

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.net.test;
+
+interface IAwEmbeddedTestServerImpl {
+
+    /** Initialize the native object. */
+    boolean initializeNative();
+
+    /** Start the server.
+     *
+     *  @return Whether the server was successfully started.
+     */
+    boolean start();
+
+    /** Add the default handlers and serve files from the provided directory relative to the
+     *  external storage directory.
+     *
+     *  @param directoryPath The path of the directory from which files should be served, relative
+     *      to the external storage directory.
+     */
+    void addDefaultHandlers(String directoryPath);
+
+    /** Register multiple request handlers.
+     *  Handlers must be registered before starting the server.
+     *
+     *  @param handlers The pointers of handlers to be registered.
+     */
+    void registerRequestHandlers(inout long[] handlers);
+
+    /** Serve files from the provided directory.
+     *
+     *  @param directoryPath The path of the directory from which files should be served.
+     */
+    void serveFilesFromDirectory(String directoryPath);
+
+    /** Get array of custom handler methods pointers.
+     *
+     *  @return The handler pointers as a long array.
+     */
+    long[] getCustomHandlers();
+
+    /** Get the full URL for the given relative URL.
+     *
+     *  @param relativeUrl The relative URL for which a full URL should be returned.
+     *  @return The URL as a String.
+     */
+    String getURL(String relativeUrl);
+
+    /** Shut down the server.
+     *
+     *  @return Whether the server was successfully shut down.
+     */
+    boolean shutdownAndWaitUntilComplete();
+
+    /** Destroy the native object. */
+    void destroy();
+
+}
+