Bug 289599 [Preferences] PreferenceStore.setToDefault fires redundant PropertyChangeEvents
bundles/org.eclipse.jface/src/org/eclipse/jface/preference/PreferenceStore.java
* 
	 * @exception java.io.IOException
	 *                if there is a problem loading this store
	 */
	public void load() throws IOException {
		if (filename == null) {
			throw new IOException("File name not specified");
		}
		FileInputStream in = new FileInputStream(filename);
		load(in);
		in.close();
	}
	/**
	 * Loads this preference store from the given input stream. Default
	 * preference values are not affected.
	 * 
	 * @param in
	 *            the input stream
	 * @exception java.io.IOException
	 *                if there is a problem loading this store
	 */
	public void load(InputStream in) throws IOException {
		properties.load(in);
		dirty = false;
	}
	/*
	 * (non-Javadoc) Method declared on IPreferenceStore.
	 */
	public boolean needsSaving() {
		return dirty;