Bug 191685 [regression]Set default value doesn't work in Report Parameter[0705]
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/ParameterDialog.java
dialog.setColumnValueList( getColumnValueList( ) );
					int status = dialog.open( );
					if ( status == Window.OK )
					{
						String selectedValue = dialog.getSelectedValue( );
						if ( selectedValue != null )
							defaultValueChooser.setText( selectedValue );
					}
					else if ( status == Window.CANCEL )
					{
						defaultValueChooser.setText( "" );
					}
				}
				else
				{
					if ( selection.equals( CHOICE_NULL_VALUE ) )
					{
						changeDefaultValue( null );
					}
					else if ( selection.equals( CHOICE_BLANK_VALUE ) )
					{
						changeDefaultValue( "" );
					}
					if ( isStatic( ) )
					{
						refreshValueTable( );
					}
				}
			}
		} );