Add method getAllHeaders to HttpUrlRequest.

components/cronet/android/java/src/org/chromium/net/HttpUrlRequest.java

 // Copyright 2014 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;
 
 import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.nio.channels.ReadableByteChannel;
+import java.util.List;
+import java.util.Map;
 
 /**
  * HTTP request (GET or POST).
  */
 public interface HttpUrlRequest {
 
     public static final int REQUEST_PRIORITY_IDLE = 0;
 
     public static final int REQUEST_PRIORITY_LOWEST = 1;
 
@@ skipping 107 matching lines @@
      * method returns 200.
      */
     int getHttpStatusCode();
 
     /**
      * Returns the response header value for the given name or {@code null} if
      * not found.
      */
     String getHeader(String name);
 
+    /**
+     * Returns an unmodifiable map of the response-header fields and values.
+     */
+    Map<String, List<String>> getAllHeaders();
 
     /**
      * Returns the exception that occurred while executing the request of null
      * if the request was successful.
      */
     IOException getException();
 }