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

third_party/protobuf/src/google/protobuf/message_lite.h

 // Protocol Buffers - Google's data interchange format
 // Copyright 2008 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
+// 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
@@ skipping 20 matching lines @@
 //  Sanjay Ghemawat, Jeff Dean, and others.
 //
 // Defines MessageLite, the abstract interface implemented by all (lite
 // and non-lite) protocol message objects.
 
 #ifndef GOOGLE_PROTOBUF_MESSAGE_LITE_H__
 #define GOOGLE_PROTOBUF_MESSAGE_LITE_H__
 
 #include <google/protobuf/stubs/common.h>
 
-
 namespace google {
 namespace protobuf {
-  class Arena;
+
 namespace io {
   class CodedInputStream;
   class CodedOutputStream;
   class ZeroCopyInputStream;
   class ZeroCopyOutputStream;
 }
 
 // Interface to light weight protocol messages.
 //
 // This interface is implemented by all protocol message objects.  Non-lite
@@ skipping 24 matching lines @@
 
   // Basic Operations ------------------------------------------------
 
   // Get the name of this message type, e.g. "foo.bar.BazProto".
   virtual string GetTypeName() const = 0;
 
   // Construct a new instance of the same type.  Ownership is passed to the
   // caller.
   virtual MessageLite* New() const = 0;
 
-  // Construct a new instance on the arena. Ownership is passed to the caller
-  // if arena is a NULL. Default implementation for backwards compatibility.
-  virtual MessageLite* New(::google::protobuf::Arena* arena) const;
-
-  // Get the arena, if any, associated with this message. Virtual method
-  // required for generic operations but most arena-related operations should
-  // use the GetArenaNoVirtual() generated-code method. Default implementation
-  // to reduce code size by avoiding the need for per-type implementations when
-  // types do not implement arena support.
-  virtual ::google::protobuf::Arena* GetArena() const { return NULL; }
-
-  // Get a pointer that may be equal to this message's arena, or may not be. If
-  // the value returned by this method is equal to some arena pointer, then this
-  // message is on that arena; however, if this message is on some arena, this
-  // method may or may not return that arena's pointer. As a tradeoff, this
-  // method may be more efficient than GetArena(). The intent is to allow
-  // underlying representations that use e.g. tagged pointers to sometimes store
-  // the arena pointer directly, and sometimes in a more indirect way, and allow
-  // a fastpath comparison against the arena pointer when it's easy to obtain.
-  virtual void* GetMaybeArenaPointer() const { return GetArena(); }
-
   // Clear all fields of the message and set them to their default values.
   // Clear() avoids freeing memory, assuming that any memory allocated
   // to hold parts of the message will be needed again to hold the next
   // message.  If you actually want to free the memory used by a Message,
   // you must delete it.
   virtual void Clear() = 0;
 
   // Quickly check if all required fields have values set.
   virtual bool IsInitialized() const = 0;
 
   // This is not implemented for Lite messages -- it just returns "(cannot
   // determine missing fields for lite message)".  However, it is implemented
   // for full messages.  See message.h.
   virtual string InitializationErrorString() const;
 
   // If |other| is the exact same class as this, calls MergeFrom().  Otherwise,
   // results are undefined (probably crash).
   virtual void CheckTypeAndMergeFrom(const MessageLite& other) = 0;
 
   // Parsing ---------------------------------------------------------
   // Methods for parsing in protocol buffer format.  Most of these are
-  // just simple wrappers around MergeFromCodedStream().  Clear() will be called
-  // before merging the input.
+  // just simple wrappers around MergeFromCodedStream().
 
-  // Fill the message with a protocol buffer parsed from the given input stream.
-  // Returns false on a read error or if the input is in the wrong format.  A
-  // successful return does not indicate the entire input is consumed, ensure
-  // you call ConsumedEntireMessage() to check that if applicable.
+  // Fill the message with a protocol buffer parsed from the given input
+  // stream.  Returns false on a read error or if the input is in the
+  // wrong format.
   bool ParseFromCodedStream(io::CodedInputStream* input);
   // Like ParseFromCodedStream(), but accepts messages that are missing
   // required fields.
   bool ParsePartialFromCodedStream(io::CodedInputStream* input);
   // Read a protocol buffer from the given zero-copy input stream.  If
   // successful, the entire input will be consumed.
   bool ParseFromZeroCopyStream(io::ZeroCopyInputStream* input);
   // Like ParseFromZeroCopyStream(), but accepts messages that are missing
   // required fields.
   bool ParsePartialFromZeroCopyStream(io::ZeroCopyInputStream* input);
   // Read a protocol buffer from the given zero-copy input stream, expecting
   // the message to be exactly "size" bytes long.  If successful, exactly
   // this many bytes will have been consumed from the input.
   bool ParseFromBoundedZeroCopyStream(io::ZeroCopyInputStream* input, int size);
   // Like ParseFromBoundedZeroCopyStream(), but accepts messages that are
   // missing required fields.
   bool ParsePartialFromBoundedZeroCopyStream(io::ZeroCopyInputStream* input,
                                              int size);
-  // Parses a protocol buffer contained in a string. Returns true on success.
-  // This function takes a string in the (non-human-readable) binary wire
-  // format, matching the encoding output by MessageLite::SerializeToString().
-  // If you'd like to convert a human-readable string into a protocol buffer
-  // object, see google::protobuf::TextFormat::ParseFromString().
+  // Parse a protocol buffer contained in a string.
   bool ParseFromString(const string& data);
   // Like ParseFromString(), but accepts messages that are missing
   // required fields.
   bool ParsePartialFromString(const string& data);
   // Parse a protocol buffer contained in an array of bytes.
   bool ParseFromArray(const void* data, int size);
   // Like ParseFromArray(), but accepts messages that are missing
   // required fields.
   bool ParsePartialFromArray(const void* data, int size);
 
@@ skipping 57 matching lines @@
 
   // Like SerializeToString(), but appends to the data to the string's existing
   // contents.  All required fields must be set.
   bool AppendToString(string* output) const;
   // Like AppendToString(), but allows missing required fields.
   bool AppendPartialToString(string* output) const;
 
   // Computes the serialized size of the message.  This recursively calls
   // ByteSize() on all embedded messages.  If a subclass does not override
   // this, it MUST override SetCachedSize().
-  //
-  // ByteSize() is generally linear in the number of fields defined for the
-  // proto.
   virtual int ByteSize() const = 0;
 
   // Serializes the message without recomputing the size.  The message must
   // not have changed since the last call to ByteSize(); if it has, the results
   // are undefined.
   virtual void SerializeWithCachedSizes(
       io::CodedOutputStream* output) const = 0;
 
   // Like SerializeWithCachedSizes, but writes directly to *target, returning
   // a pointer to the byte immediately after the last byte written.  "target"
@@ skipping 14 matching lines @@
   virtual int GetCachedSize() const = 0;
 
  private:
   GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(MessageLite);
 };
 
 }  // namespace protobuf
 
 }  // namespace google
 #endif  // GOOGLE_PROTOBUF_MESSAGE_LITE_H__