Bug 232048 [Viewers] binary incompatibility (adding public fields) reported against jface.viewers
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/CellEditor.java
* @see #setValueValid(boolean)
	 */
	public boolean isValueValid() {
		return valid;
	}
	/**
	 * Processes a key release event that occurred in this cell editor.
	 * <p>
	 * The default implementation of this framework method cancels editing when
	 * the ESC key is pressed. When the RETURN key is pressed the current value
	 * is applied and the cell editor deactivates. Subclasses should call this
	 * method at appropriate times. Subclasses may also extend or reimplement.
	 * </p>
	 *
	 * @param keyEvent
	 *            the key event
	 */
	protected void keyReleaseOccured(KeyEvent keyEvent) {
		if (keyEvent.character == '\u001b') { 
			fireCancelEditor();
		} else if (keyEvent.character == '\r') { 
			fireApplyEditorValue();
			deactivate();
		}
	}
	/**
	 * Processes a focus lost event that occurred in this cell editor.
	 * <p>
	 * The default implementation of this framework method applies the current
	 * value and deactivates the cell editor. Subclasses should call this method