[Cronet] Add callback wrapper classes to enforce API version checking.

components/cronet/android/java/src/org/chromium/net/impl/CronetUploadDataStream.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.impl;
 
 import android.annotation.SuppressLint;
 import android.util.Log;
 
 import org.chromium.base.VisibleForTesting;
@@ skipping 18 matching lines @@
  * It is called by the UploadDataStreamAdapter on the network thread, but calls
  * into the UploadDataSink and the UploadDataStreamAdapter on the Executor
  * passed into its constructor.
  */
 @JNINamespace("cronet")
 @VisibleForTesting
 public final class CronetUploadDataStream extends UploadDataSink {
     private static final String TAG = "CronetUploadDataStream";
     // These are never changed, once a request starts.
     private final Executor mExecutor;
-    private final UploadDataProvider mDataProvider;
+    private final VersionSafeCallbacks.UploadDataProviderWrapper mDataProvider;

[kapishnikov, 2016/11/18 16:32:57]

Same here. We should keep UploadDataProvider. Applies to other places.

[pauljensen, 2016/11/18 19:18:07]

I think that defeats the purpose of this CL.  Users of mDataProvider would then
be calling directly through the API class...which would fail if the API class
was too old and was missing new members.

[kapishnikov, 2016/11/18 19:39:15]

Acknowledged.

     private long mLength;
     private long mRemainingLength;
     private CronetUrlRequest mRequest;
 
     // Reusable read task, to reduce redundant memory allocation.
     private final Runnable mReadTask = new Runnable() {
         @Override
         public void run() {
             synchronized (mLock) {
                 if (mUploadDataStreamAdapter == 0) {
@@ skipping 41 matching lines @@
     private boolean mDestroyAdapterPostponed = false;
     private Runnable mOnDestroyedCallbackForTesting;
 
     /**
      * Constructs a CronetUploadDataStream.
      * @param dataProvider the UploadDataProvider to read data from.
      * @param executor the Executor to execute UploadDataProvider tasks.
      */
     public CronetUploadDataStream(UploadDataProvider dataProvider, Executor executor) {
         mExecutor = executor;
-        mDataProvider = dataProvider;
+        mDataProvider = new VersionSafeCallbacks.UploadDataProviderWrapper(dataProvider);
     }
 
     /**
      * Called by native code to make the UploadDataProvider read data into
      * {@code byteBuffer}.
      */
     @SuppressWarnings("unused")
     @CalledByNative
     void readData(ByteBuffer byteBuffer) {
         mByteBuffer = byteBuffer;
@@ skipping 274 matching lines @@
 
     @NativeClassQualifiedName("CronetUploadDataStreamAdapter")
     private native void nativeOnReadSucceeded(long nativePtr, int bytesRead, boolean finalChunk);
 
     @NativeClassQualifiedName("CronetUploadDataStreamAdapter")
     private native void nativeOnRewindSucceeded(long nativePtr);
 
     @NativeClassQualifiedName("CronetUploadDataStreamAdapter")
     private static native void nativeDestroy(long nativePtr);
 }