Revert https://codereview.chromium.org/1291903002 (protobuf roll).

third_party/protobuf/javanano/src/main/java/com/google/protobuf/nano/ExtendableMessageNano.java

Index: third_party/protobuf/javanano/src/main/java/com/google/protobuf/nano/ExtendableMessageNano.java
diff --git a/third_party/protobuf/javanano/src/main/java/com/google/protobuf/nano/ExtendableMessageNano.java b/third_party/protobuf/javanano/src/main/java/com/google/protobuf/nano/ExtendableMessageNano.java
deleted file mode 100644
index 87973d76f07034249d833abbc5e4dfb4236eb238..0000000000000000000000000000000000000000
--- a/third_party/protobuf/javanano/src/main/java/com/google/protobuf/nano/ExtendableMessageNano.java
+++ /dev/null
@@ -1,169 +0,0 @@
-// Protocol Buffers - Google's data interchange format
-// Copyright 2013 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
-//
-// 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 com.google.protobuf.nano;
-
-import java.io.IOException;
-
-/**
- * Base class of those Protocol Buffer messages that need to store unknown fields,
- * such as extensions.
- */
-public abstract class ExtendableMessageNano<M extends ExtendableMessageNano<M>>
-        extends MessageNano {
-    /**
-     * A container for fields unknown to the message, including extensions. Extension fields can
-     * can be accessed through the {@link #getExtension} and {@link #setExtension} methods.
-     */
-    protected FieldArray unknownFieldData;
-
-    @Override
-    protected int computeSerializedSize() {
-        int size = 0;
-        if (unknownFieldData != null) {
-            for (int i = 0; i < unknownFieldData.size(); i++) {
-                FieldData field = unknownFieldData.dataAt(i);
-                size += field.computeSerializedSize();
-            }
-        }
-        return size;
-    }
-
-    @Override
-    public void writeTo(CodedOutputByteBufferNano output) throws IOException {
-        if (unknownFieldData == null) {
-            return;
-        }
-        for (int i = 0; i < unknownFieldData.size(); i++) {
-            FieldData field = unknownFieldData.dataAt(i);
-            field.writeTo(output);
-        }
-    }
-
-    /**
-     * Checks if there is a value stored for the specified extension in this
-     * message.
-     */
-    public final boolean hasExtension(Extension<M, ?> extension) {
-        if (unknownFieldData == null) {
-            return false;
-        }
-        FieldData field = unknownFieldData.get(WireFormatNano.getTagFieldNumber(extension.tag));
-        return field != null;
-    }
-
-    /**
-     * Gets the value stored in the specified extension of this message.
-     */
-    public final <T> T getExtension(Extension<M, T> extension) {
-        if (unknownFieldData == null) {
-            return null;
-        }
-        FieldData field = unknownFieldData.get(WireFormatNano.getTagFieldNumber(extension.tag));
-        return field == null ? null : field.getValue(extension);
-    }
-
-    /**
-     * Sets the value of the specified extension of this message.
-     */
-    public final <T> M setExtension(Extension<M, T> extension, T value) {
-        int fieldNumber = WireFormatNano.getTagFieldNumber(extension.tag);
-        if (value == null) {
-            if (unknownFieldData != null) {
-                unknownFieldData.remove(fieldNumber);
-                if (unknownFieldData.isEmpty()) {
-                    unknownFieldData = null;
-                }
-            }
-        } else {
-            FieldData field = null;
-            if (unknownFieldData == null) {
-                unknownFieldData = new FieldArray();
-            } else {
-                field = unknownFieldData.get(fieldNumber);
-            }
-            if (field == null) {
-                unknownFieldData.put(fieldNumber, new FieldData(extension, value));
-            } else {
-                field.setValue(extension, value);
-            }
-        }
-
-        @SuppressWarnings("unchecked") // Generated code should guarantee type safety
-        M typedThis = (M) this;
-        return typedThis;
-    }
-
-    /**
-     * Stores the binary data of an unknown field.
-     *
-     * <p>Generated messages will call this for unknown fields if the store_unknown_fields
-     * option is on.
-     *
-     * <p>Note that the tag might be a end-group tag (rather than the start of an unknown field) in
-     * which case we do not want to add an unknown field entry.
-     *
-     * @param input the input buffer.
-     * @param tag the tag of the field.
-
-     * @return {@literal true} unless the tag is an end-group tag.
-     */
-    protected final boolean storeUnknownField(CodedInputByteBufferNano input, int tag)
-            throws IOException {
-        int startPos = input.getPosition();
-        if (!input.skipField(tag)) {
-            return false;  // This wasn't an unknown field, it's an end-group tag.
-        }
-        int fieldNumber = WireFormatNano.getTagFieldNumber(tag);
-        int endPos = input.getPosition();
-        byte[] bytes = input.getData(startPos, endPos - startPos);
-        UnknownFieldData unknownField = new UnknownFieldData(tag, bytes);
-
-        FieldData field = null;
-        if (unknownFieldData == null) {
-            unknownFieldData = new FieldArray();
-        } else {
-            field = unknownFieldData.get(fieldNumber);
-        }
-        if (field == null) {
-            field = new FieldData();
-            unknownFieldData.put(fieldNumber, field);
-        }
-        field.addUnknownField(unknownField);
-        return true;
-    }
-
-    @Override
-    public M clone() throws CloneNotSupportedException {
-        M cloned = (M) super.clone();
-        InternalNano.cloneUnknownFieldData(this, cloned);
-        return cloned;
-    }
-}