Bug 161425 [Viewers] TableTreeViewer => EditingSupport broken
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/TableTreeViewer.java
int columns = getColumnCount();
			if (columns == 0) {
				
				
				columnToEdit = 0;
			} else {
				columnToEdit = -1;
				for (int i = 0; i < columns; i++) {
					Rectangle bounds = getBounds(tableItem, i);
					if (bounds.contains(event.x, event.y)) {
						columnToEdit = i;
						break;
					}
				}
				if (columnToEdit == -1) {
					return;
				}
			}
			columnNumber = columnToEdit;
			activateCellEditor();
		}
		/**
		 * Deactivates the currently active cell editor.
		 */
		public void applyEditorValue() {
			CellEditor c = this.cellEditor;
			if (c != null) {