Bug 132798 [Field Assist] - Pressing Backspace at offset 0 should not reload field assist popup
N20060322-0010. After migrating the Find/Replace dialog to the new field assist support I found the following blooper: pressing the Backspace key at offset 0 reloads the field assist popup. Test Case: 1. in a text editor press Ctrl+F 2. enable regex search 3. in the Find filed press Ctrl+Space 4. continuously press Backspace ==> each time the proposal list is reloaded.
bundles/org.eclipse.jface/src/org/eclipse/jface/fieldassist/ContentProposalAdapter.java
* 
		 * @return the return code
		 * 
		 * @see org.eclipse.jface.window.Window#open()
		 */
		public int open() {
			int value = super.open();
			if (popupCloser == null) {
				popupCloser = new PopupCloserListener();
			}
			popupCloser.installListeners();
			showProposalDescription(getSelectedProposal().getDescription());
			return value;
		}
		/**
		 * Closes this popup. This method is extended to remove the control
		 * listener.
		 * 
		 * @return <code>true</code> if the window is (or was already) closed,
		 *         and <code>false</code> if it is still open
		 */
		public boolean close() {
			popupCloser.removeListeners();
			if (infoPopup != null) {
				infoPopup.close();
			}
			return super.close();
		}
		/*
		 * Get the proposals from the proposal provider. The provider may or may