Bug 78666 [KeyBindings] errors: No warning if keybinding definitions collide
Using 3.1 M3, if I define a keybinding in the default "windows" context and with keybinding of "CTRL+B" or "CTRL+U", the keybindings are silently removed. In the very least, the conflict should be logged. Ideally, the user would also see the collision in the keybindings preference page. In this case, I think it's better to show some information than to just kill these mapping and not explain why. Eclipse is a dynamic platform. There are lots of scenarios where keybindings get added into a configuration and start conflicting with previously working keybindings.
bundles/org.eclipse.jface/src/org/eclipse/jface/bindings/BindingManager.java
* Constructs a new instance of <code>BindingManager</code>.
	 * </p>
	 * <p>
	 * This method completes in amortized constant time (O(1)).
	 * </p>
	 * 
	 * @param contextManager
	 *            The context manager that will support this binding manager.
	 *            This value must not be <code>null</code>.
	 * @param commandManager
	 *            The command manager that will support this binding manager.
	 *            This value must not be <code>null</code>.
	 */
	public BindingManager(final ContextManager contextManager,
			final CommandManager commandManager) {
		if (contextManager == null) {
			throw new NullPointerException(
					"A binding manager requires a context manager"); 
		}
		if (commandManager == null) {
			throw new NullPointerException(
					"A binding manager requires a command manager"); 
		}
		this.contextManager = contextManager;
		contextManager.addContextManagerListener(this);
		this.commandManager = commandManager;
	}
	/**
	 * <p>
	 * Adds a single new binding to the existing array of bindings. If the array