Bug 1722394 - Slim AccAttributes::AttrValueType by removing nsString. r=morgan

Differential Revision: https://phabricator.services.mozilla.com/D120897

accessible/base/AccAttributes.cpp

@@ -23,7 +23,6 @@ void AccAttributes::StringFromValueAndName(nsAtom* aAttrName,
   aValueString.Truncate();
 
   aValue.match(
-      [&aValueString](const nsString& val) { aValueString.Assign(val); },
       [&aValueString](const bool& val) {
         aValueString.Assign(val ? u"true" : u"false");
       },

accessible/base/AccAttributes.h

@@ -38,8 +38,8 @@ struct Color {
 class AccAttributes {
   friend struct IPC::ParamTraits<AccAttributes*>;
 
-  using AttrValueType = Variant<nsString, bool, float, int32_t, RefPtr<nsAtom>,
-                                CSSCoord, FontSize, Color>;
+  using AttrValueType =
+      Variant<bool, float, int32_t, RefPtr<nsAtom>, CSSCoord, FontSize, Color>;
   using AtomVariantMap = nsTHashMap<nsRefPtrHashKey<nsAtom>, AttrValueType>;
 
  protected:
@@ -60,7 +60,8 @@ class AccAttributes {
       mData.InsertOrUpdate(aAttrName, AsVariant(RefPtr<nsAtom>(aAttrValue)));
     } else if constexpr (std::is_base_of_v<nsAString, T> ||
                          std::is_base_of_v<nsLiteralString, T>) {
-      mData.InsertOrUpdate(aAttrName, AsVariant(nsString(aAttrValue)));
+      RefPtr<nsAtom> atomValue = NS_Atomize(aAttrValue);
+      mData.InsertOrUpdate(aAttrName, AsVariant(atomValue));
     } else {
       mData.InsertOrUpdate(aAttrName, AsVariant(aAttrValue));
     }