Bug 135497 Data Type is not correct when "Generate All" for Data item
Description: Create a sample datasource and dataset. Insert a data into layout, bind with the dataset.Click "Generate All" to get the Data Binding columns, but the displayed data type is not consistent with the actual one.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/actions/BaseInsertMenuAction.java
this.insertType = type;
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.gef.ui.actions.WorkbenchPartAction#calculateEnabled()
	 */
	protected boolean calculateEnabled( )
	{
		slotHandle = getDefaultSlotHandle( insertType );
		return DNDUtil.handleValidateTargetCanContainType( slotHandle,
				insertType )
				&& DNDUtil.handleValidateTargetCanContainMore( slotHandle, 0 );
	}
	/**
	 * Returns the container slotHandle.
	 * 
	 */
	private SlotHandle getDefaultSlotHandle( String insertType )
	{
		IStructuredSelection models = InsertInLayoutUtil.editPart2Model( getSelection( ) );
		if ( models.isEmpty( ) )
		{
			return null;
		}
		model = models.getFirstElement( );
		if ( model instanceof SlotHandle )
		{
			return (SlotHandle) model;
		}