Bug 289599 [Preferences] PreferenceStore.setToDefault fires redundant PropertyChangeEvents
bundles/org.eclipse.jface/src/org/eclipse/jface/preference/PreferenceStore.java
}
	/**
	 * Saves the non-default-valued preferences known to this preference store
	 * to the file from which they were originally loaded.
	 * 
	 * @exception java.io.IOException
	 *                if there is a problem saving this store
	 */
	public void save() throws IOException {
		if (filename == null) {
			throw new IOException("File name not specified");
		}
		FileOutputStream out = null;
		try {
			out = new FileOutputStream(filename);
			save(out, null);
		} finally {
			if (out != null) {
				out.close();
			}
		}
	}
	/**
	 * Saves this preference store to the given output stream. The given string
	 * is inserted as header information.
	 * 
	 * @param out
	 *            the output stream
	 * @param header
	 *            the header