MAINT-1180 FIXED Cannot delete object description.

indra/llui/lllineeditor.cpp

@@ -253,6 +253,7 @@ void LLLineEditor::onCommit()
 
 	setControlValue(getValue());
 	LLUICtrl::onCommit();
+	resetDirty();
 
 	// Selection on commit needs to be turned off when evaluating maths
 	// expressions, to allow indication of the error position