[Android] Add ChromiumNetTestSupport.apk for the java EmbeddedTestServer.

net/test/android/javatests/src/org/chromium/net/test/IEmbeddedTestServerImpl.aidl

+// Copyright 2015 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 IEmbeddedTestServerImpl {
+
+    /** Initialize the native object. */
+    void initializeNative();
+
+    /** Starts the server.

[mef, 2015/12/02 16:00:08]

nit: Starts -> Start

[jbudorick, 2015/12/03 00:03:44]

Done.

+     *
+     *  @return Whether the server was successfully started.
+     */
+    boolean start();
+
+    /** Serve files from the provided directory.
+     *
+     *  @param directoryPath The path of the directory from which files should be served.
+     */
+    void serveFilesFromDirectory(String directoryPath); 
+
+    /** 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();
+
+}
+