Fix an exception when right-clicking in the CSV field mapping table without active selection (#2219)

Author: dmoagx

Source/SPFieldMapperController.m

@@ -1604,15 +1604,21 @@ - (void)validateImportButton
  */
 - (BOOL)validateMenuItem:(NSMenuItem *)menuItem
 {
-
 	NSInteger row = [fieldMapperTableView selectedRow];
 
 	// Hide/display Remove New Column menu item
 	[[[fieldMapperTableView menu] itemAtIndex:3] setHidden:([toBeEditedRowIndexes containsIndex:row]) ? NO : YES];
 
 	if (newTableMode && [menuItem action] == @selector(setAllTypesTo:)) {
-		NSString *orgTitle = [[menuItem title] substringToIndex:[[menuItem title] rangeOfString:@":"].location];
-		[menuItem setTitle:[NSString stringWithFormat:@"%@: %@", orgTitle, [fieldMappingTableTypes objectAtIndex:row]]];
+		if(row > -1) { // row == -1 on empty selection
+			NSString *orgTitle = [[menuItem title] substringToIndex:[[menuItem title] rangeOfString:@":"].location];
+			[menuItem setTitle:[NSString stringWithFormat:@"%@: %@", orgTitle, [fieldMappingTableTypes objectAtIndex:row]]];
+			[menuItem setHidden:NO];
+		}
+		else {
+			[menuItem setHidden:YES];
+			return NO;
+		}
 	}
 	else if (!newTableMode && [menuItem action] == @selector(insertNULLValue:)) {
 		return ([[globalValuesTableView selectedRowIndexes] count] == 1) ? YES : NO;