Add new Cronet exception class for QUIC errors

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

 // Copyright 2014 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.io.IOException;
 
 /**
  * Exception passed to {@link UrlRequest.Callback#onFailed UrlRequest.Callback.onFailed()} when:
  * <ul>
  * <li>{@link UrlRequest.Callback} or {@link UploadDataProvider} method throws an exception. In this
  *     case {@link IOException#getCause getCause()} can be used to find the thrown exception.
  *     {@link #getErrorCode} will return {@link #ERROR_LISTENER_EXCEPTION_THROWN}.
  * <li>Cronet fails to process a network request. In this case
  *     {@link #getErrorCode} and {@link #getCronetInternalErrorCode} can be used to get more
- *     information about the specific type of failure.
+ *     information about the specific type of failure. If {@link #getCronetInternalErrorCode}
+ *     returns QUIC_PROTOCOL_ERROR, this exception can be cast to a {@link QuicException}

[pauljensen, 2016/06/30 17:35:12]

It's quite awkward to reference a value here without an easy way of knowing how
to use that value. (users would have to know to click the
getCronetInternalErrorCode link and then click the link to the errors and then
grep for QUIC_PROTOCOL_ERROR and then define their own constant in Java for this
value)  I'd propose adding ERROR_QUIC_PROTOCOL_FAILED to this class.

[mgersh, 2016/06/30 22:55:53]

Done. (Was the different name just to avoid saying "ERROR" twice?)

+ *     which can provide further details.
  * </ul>
  */
 public class UrlRequestException extends IOException {
     /**
      * Error code indicating this class wraps an exception thrown by {@link UrlRequest.Callback} or
      * {@link UploadDataProvider}. Wrapped exception can be retrieved using
      * {@link IOException#getCause}.
      */
     public static final int ERROR_LISTENER_EXCEPTION_THROWN =
             UrlRequestError.LISTENER_EXCEPTION_THROWN;
@@ skipping 120 matching lines @@
                 return false;
             case ERROR_NETWORK_CHANGED:
             case ERROR_TIMED_OUT:
             case ERROR_CONNECTION_CLOSED:
             case ERROR_CONNECTION_TIMED_OUT:
             case ERROR_CONNECTION_RESET:
                 return true;
         }
     }
 }