/usr/include/thunderbird/nsStubMutationObserver.h is in thunderbird-dev 1:52.8.0-1~deb8u1.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35  | /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/*
 * nsStubMutationObserver is an implementation of the nsIMutationObserver
 * interface (except for the methods on nsISupports) that is intended to be
 * used as a base class within the content/layout library.  All methods do
 * nothing.
 */
#ifndef nsStubMutationObserver_h_
#define nsStubMutationObserver_h_
#include "nsIMutationObserver.h"
/**
 * There are two advantages to inheriting from nsStubMutationObserver
 * rather than directly from nsIMutationObserver:
 *  1. smaller compiled code size (since there's no need for the code
 *     for the empty virtual function implementations for every
 *     nsIMutationObserver implementation)
 *  2. the performance of document's loop over observers benefits from
 *     the fact that more of the functions called are the same (which
 *     can reduce instruction cache misses and perhaps improve branch
 *     prediction)
 */
class nsStubMutationObserver : public nsIMutationObserver {
public:
  NS_DECL_NSIMUTATIONOBSERVER
};
#endif /* !defined(nsStubMutationObserver_h_) */
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