Bug 134750 [DataBinding] TextObservableValue throws NPE on change if the intial model value is null
When binding a Text to a model attribute that has an intial value of null ObservableTextValue throws a NPE when updating the view. In "updateListener" it assumes that oldValue != null. I'll attach a JUnit that throws the Exception.
bundles/org.eclipse.jface.databinding/src/org/eclipse/jface/internal/databinding/internal/swt/TextObservableValue.java
public void handleEvent(Event event) {
					if (!updating) {
						bufferedValue = text.getText();
					}
				}
			});
		}
		verifyListener = new VerifyListener() {
			public void verifyText(VerifyEvent e) {
				if (!updating) {
					String currentText = TextObservableValue.this.text
							.getText();
					String newText = currentText.substring(0, e.start) + e.text
							+ currentText.substring(e.end);
					if (!fireValueChanging(Diffs.createValueDiff(currentText,
							newText))) {
						e.doit = false;
					}
				}
			}
		};
		text.addVerifyListener(verifyListener);
		keyListener = new KeyListener() {
			public void keyPressed(KeyEvent e) {
				if (e.character == SWT.ESC && bufferedValue != null) {
					
					text.setText(bufferedValue);
				}
			}
			public void keyReleased(KeyEvent e) {