[Cronet] Expose quic_user_agent_id and quic_prefer_aes config options.

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

 // 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;
 
 import android.content.Context;
 import android.support.annotation.IntDef;
 import android.support.annotation.Nullable;
 import android.util.Log;
@@ skipping 113 matching lines @@
             mContext = context;
             setLibraryName("cronet");
             enableLegacyMode(false);
             enableQUIC(false);
             enableHTTP2(true);
             enableSDCH(false);
             enableHttpCache(HTTP_CACHE_DISABLED, 0);
         }
 
         /**
-         * Constructs a User-Agent string including Cronet version, and
-         * application name and version.
+         * Constructs a User-Agent string including application name and version,
+         * system build version, model and id, and Cronet version.
          *
          * @return User-Agent string.
          */
         public String getDefaultUserAgent() {
             return UserAgent.from(mContext);
         }
 
         /**
          * Overrides the User-Agent header for all requests. An explicitly
          * set User-Agent header (set using
@@ skipping 87 matching lines @@
         void loadLibrary() {
             if (mLibraryLoader == null) {
                 System.loadLibrary(mLibraryName);
             } else {
                 mLibraryLoader.loadLibrary(mLibraryName);
             }
         }
 
         /**
          * Sets whether <a href="https://www.chromium.org/quic">QUIC</a> protocol
-         * is enabled. Defaults to disabled.
+         * is enabled. Defaults to disabled. If QUIC is enabled, then QUIC User Agent Id
+         * containing application name and Cronet version is sent to the server.
          * @param value {@code true} to enable QUIC, {@code false} to disable.
          * @return the builder to facilitate chaining.
          */
         public Builder enableQUIC(boolean value) {
             mQuicEnabled = value;
             return this;
         }
 
         boolean quicEnabled() {
             return mQuicEnabled;
         }
 
         /**
+         * Constructs default QUIC User Agent Id string including application name
+         * and Cronet version. Returns empty string if QUIC is not enabled.
+         *
+         * @return QUIC User Agent ID string.
+         */
+        String getDefaultQuicUserAgentId() {
+            return mQuicEnabled ? UserAgent.getQuicUserAgentIdFrom(mContext) : "";
+        }
+
+        /**
          * Sets whether <a href="https://tools.ietf.org/html/rfc7540">HTTP/2</a>
          * protocol is enabled. Defaults to enabled.
          * @param value {@code true} to enable HTTP/2, {@code false} to disable.
          * @return the builder to facilitate chaining.
          */
         public Builder enableHTTP2(boolean value) {
             mHttp2Enabled = value;
             return this;
         }
 
@@ skipping 822 matching lines @@
      */
     @Deprecated
     public interface RequestFinishedListener { // TODO(klm): Add a convenience abstract class.
         /**
          * Invoked with request info.
          * @param requestInfo {@link UrlRequestInfo} for finished request.
          */
         void onRequestFinished(UrlRequestInfo requestInfo);
     }
 }