Update protobuf to r428, part 1.

third_party/protobuf/java/src/main/java/com/google/protobuf/InvalidProtocolBufferException.java

Index: third_party/protobuf/java/src/main/java/com/google/protobuf/InvalidProtocolBufferException.java
===================================================================
--- third_party/protobuf/java/src/main/java/com/google/protobuf/InvalidProtocolBufferException.java	(revision 216642)
+++ third_party/protobuf/java/src/main/java/com/google/protobuf/InvalidProtocolBufferException.java	(working copy)
@@ -40,11 +40,32 @@
  */
 public class InvalidProtocolBufferException extends IOException {
   private static final long serialVersionUID = -1616151763072450476L;
+  private MessageLite unfinishedMessage = null;
 
   public InvalidProtocolBufferException(final String description) {
     super(description);
   }
 
+  /**
+   * Attaches an unfinished message to the exception to support best-effort
+   * parsing in {@code Parser} interface.
+   *
+   * @return this
+   */
+  public InvalidProtocolBufferException setUnfinishedMessage(
+      MessageLite unfinishedMessage) {
+    this.unfinishedMessage = unfinishedMessage;
+    return this;
+  }
+
+  /**
+   * Returns the unfinished message attached to the exception, or null if
+   * no message is attached.
+   */
+  public MessageLite getUnfinishedMessage() {
+    return unfinishedMessage;
+  }
+
   static InvalidProtocolBufferException truncatedMessage() {
     return new InvalidProtocolBufferException(
       "While parsing a protocol message, the input ended unexpectedly " +