Simpler return value of HashTable::add/HashMap:add and others

Source/platform/fonts/mac/SimpleFontDataMac.mm

Index: Source/platform/fonts/mac/SimpleFontDataMac.mm
diff --git a/Source/platform/fonts/mac/SimpleFontDataMac.mm b/Source/platform/fonts/mac/SimpleFontDataMac.mm
index 72eb49cb40f502d4720491dbfe8661b0741c8646..769344a88767333f6490a99c420c8ad56b6de93d 100644
--- a/Source/platform/fonts/mac/SimpleFontDataMac.mm
+++ b/Source/platform/fonts/mac/SimpleFontDataMac.mm
@@ -419,7 +419,7 @@ bool SimpleFontData::canRenderCombiningCharacterSequence(const UChar* characters
 
     WTF::HashMap<String, bool>::AddResult addResult = m_combiningCharacterSequenceSupport->add(String(characters, length), false);
     if (!addResult.isNewEntry)
-        return addResult.iterator->value;
+        return addResult.storedValue->value;
 
     RetainPtr<CGFontRef> cgFont(AdoptCF, CTFontCopyGraphicsFont(platformData().ctFont(), 0));
 
@@ -439,7 +439,7 @@ bool SimpleFontData::canRenderCombiningCharacterSequence(const UChar* characters
             return false;
     }
 
-    addResult.iterator->value = true;
+    addResult.storedValue->value = true;
     return true;
 }