[Cronet] Fix CronetFixedModeOutputStream to not write more bytes than specified

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.annotation.SuppressLint;
 import android.content.Context;
 import android.net.http.HttpResponseCache;
 import android.support.annotation.IntDef;
 import android.support.annotation.Nullable;
+import android.support.annotation.VisibleForTesting;
 import android.util.Log;
 
 import java.io.File;
 import java.io.IOException;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.lang.reflect.Constructor;
 import java.net.IDN;
 import java.net.Proxy;
 import java.net.URL;
@@ skipping 561 matching lines @@
         String experimentalOptions() {
             return mExperimentalOptions;
         }
 
         /**
          * Sets a native MockCertVerifier for testing. See
          * {@code MockCertVerifier.createMockCertVerifier} for a method that
          * can be used to create a MockCertVerifier.
          * @param mockCertVerifier pointer to native MockCertVerifier.
          * @return the builder to facilitate chaining.
+         * @hide
          */
-        Builder setMockCertVerifierForTesting(long mockCertVerifier) {
+        @VisibleForTesting
+        public Builder setMockCertVerifierForTesting(long mockCertVerifier) {
             mMockCertVerifier = mockCertVerifier;
             return this;
         }
 
         long mockCertVerifier() {
             return mMockCertVerifier;
         }
 
         /**
          * Returns {@link Context} for builder.
@@ skipping 505 matching lines @@
      * @hide as it's a prototype.
      */
     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);
     }
 }