[Cronet] Add ExperimentalCronetEngine.Builder.setThreadPriority() API

components/cronet/android/api/src/org/chromium/net/ICronetEngineBuilder.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 java.util.Date;
 import java.util.Set;
 
 /**
  * Defines methods that the actual implementation of {@link CronetEngine.Builder} has to implement.
@@ skipping 34 matching lines @@
     // the client.
 
     public ICronetEngineBuilder enableNetworkQualityEstimator(boolean value) {
         return this;
     }
 
     public ICronetEngineBuilder setCertVerifierData(String certVerifierData) {
         return this;
     }
 
+    public ICronetEngineBuilder setThreadPriority(int priority) {
+        return this;
+    }
 }