=all #13783 replace protobuf dependency by embedded version

- created new subproject akka-protobuf (and added COPYING and LICENSE)
- renamed com.google.protobuf -> akka.protobuf everywhere
- also added such renaming step to the results of protoc compilation in
  project/Protobuf.scala
- had to include transcriptions of Netty’s ProtobufEncoder/Decoder to
  make multi-node-testkit compile again

akka-protobuf/src/main/java/akka/protobuf/InvalidProtocolBufferException.java

@@ -0,0 +1,114 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package akka.protobuf;
+
+import java.io.IOException;
+
+/**
+ * Thrown when a protocol message being parsed is invalid in some way,
+ * e.g. it contains a malformed varint or a negative byte length.
+ *
+ * @author kenton@google.com Kenton Varda
+ */
+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 " +
+      "in the middle of a field.  This could mean either than the " +
+      "input has been truncated or that an embedded message " +
+      "misreported its own length.");
+  }
+
+  static InvalidProtocolBufferException negativeSize() {
+    return new InvalidProtocolBufferException(
+      "CodedInputStream encountered an embedded string or message " +
+      "which claimed to have negative size.");
+  }
+
+  static InvalidProtocolBufferException malformedVarint() {
+    return new InvalidProtocolBufferException(
+      "CodedInputStream encountered a malformed varint.");
+  }
+
+  static InvalidProtocolBufferException invalidTag() {
+    return new InvalidProtocolBufferException(
+      "Protocol message contained an invalid tag (zero).");
+  }
+
+  static InvalidProtocolBufferException invalidEndTag() {
+    return new InvalidProtocolBufferException(
+      "Protocol message end-group tag did not match expected tag.");
+  }
+
+  static InvalidProtocolBufferException invalidWireType() {
+    return new InvalidProtocolBufferException(
+      "Protocol message tag had invalid wire type.");
+  }
+
+  static InvalidProtocolBufferException recursionLimitExceeded() {
+    return new InvalidProtocolBufferException(
+      "Protocol message had too many levels of nesting.  May be malicious.  " +
+      "Use CodedInputStream.setRecursionLimit() to increase the depth limit.");
+  }
+
+  static InvalidProtocolBufferException sizeLimitExceeded() {
+    return new InvalidProtocolBufferException(
+      "Protocol message was too large.  May be malicious.  " +
+      "Use CodedInputStream.setSizeLimit() to increase the size limit.");
+  }
+}