[Cronet] Expose ExperimentalCronetEngine.Builder.getBuilderDelegate() for tests

components/cronet/android/api/src/org/chromium/net/ExperimentalCronetEngine.java

 // Copyright 2016 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 android.content.Context;
 import android.support.annotation.VisibleForTesting;
 
 import java.io.IOException;
 import java.net.Proxy;
@@ skipping 163 matching lines @@
          * Sets experimental options to be used in Cronet.
          *
          * @param options JSON formatted experimental options.
          * @return the builder to facilitate chaining.
          */
         public Builder setExperimentalOptions(String options) {
             mBuilderDelegate.setExperimentalOptions(options);
             return this;
         }
 
+        /**
+         * Returns delegate, only for testing.
+         * @hide
+         */
         @VisibleForTesting
-        ICronetEngineBuilder getBuilderDelegate() {
+        public ICronetEngineBuilder getBuilderDelegate() {
             return mBuilderDelegate;
         }
 
         // To support method chaining, override superclass methods to return an
         // instance of this class instead of the parent.
 
         @Override
         public Builder setUserAgent(String userAgent) {
             super.setUserAgent(userAgent);
             return this;
@@ skipping 242 matching lines @@
      * {@link #CONNECTION_METRIC_UNKNOWN} if the value is
      * unavailable. This must be called after
      * {@link Builder#enableNetworkQualityEstimator}, and will
      * throw an exception otherwise.
      * @return Estimate of the downstream throughput in kilobits per second.
      */
     public int getDownstreamThroughputKbps() {
         return CONNECTION_METRIC_UNKNOWN;
     }
 }