Return boolean for the replace method in DOMTokenList

The specification for DOMTokenList's replace() method
which would make it return a boolean.

Indicating true if a token was replaced, and false otherwise.

Bug: 820988
Signed-off-by: Yuhong Sha <yuhong.sha@samsung.com>
Change-Id: I8e500a74a2504e13522c4e85b17d441cd2d4299f
Reviewed-on: https://chromium-review.googlesource.com/965683Reviewed-by: Kent Tamura <tkent@chromium.org>
Reviewed-by: Hayato Ito <hayato@chromium.org>
Commit-Queue: Kent Tamura <tkent@chromium.org>
Cr-Commit-Position: refs/heads/master@{#545018}

third_party/WebKit/Source/core/dom/DOMTokenList.cpp

@@ -173,20 +173,20 @@ bool DOMTokenList::toggle(const AtomicString& token,
 }
 
 // https://dom.spec.whatwg.org/#dom-domtokenlist-replace
-void DOMTokenList::replace(const AtomicString& token,
+bool DOMTokenList::replace(const AtomicString& token,
                            const AtomicString& new_token,
                            ExceptionState& exception_state) {
   // 1. If either token or newToken is the empty string, then throw a
   // SyntaxError.
   if (!CheckEmptyToken(token, exception_state) ||
       !CheckEmptyToken(new_token, exception_state))
-    return;
+    return false;
 
   // 2. If either token or newToken contains any ASCII whitespace, then throw an
   // InvalidCharacterError.
   if (!CheckTokenWithWhitespace(token, exception_state) ||
       !CheckTokenWithWhitespace(new_token, exception_state))
-    return;
+    return false;
 
   // https://infra.spec.whatwg.org/#set-replace
   // To replace within an ordered set set, given item and replacement: if set
@@ -217,13 +217,14 @@ void DOMTokenList::replace(const AtomicString& token,
     }
   }
 
-  // TODO(tkent): This check doesn't conform to the DOM specification, but it's
-  // interoperable with Firefox and Safari.
-  // https://github.com/whatwg/dom/issues/462
+  // 3. If context object's token set does not contain token, then return false.
   if (!did_update)
-    return;
+    return false;
 
   UpdateWithTokenSet(token_set_);
+
+  // 6. Return true.
+  return true;
 }
 
 bool DOMTokenList::supports(const AtomicString& token,

third_party/WebKit/Source/core/dom/DOMTokenList.h

@@ -56,7 +56,7 @@ class CORE_EXPORT DOMTokenList : public ScriptWrappable {
   void remove(const Vector<String>&, ExceptionState&);
   bool toggle(const AtomicString&, ExceptionState&);
   bool toggle(const AtomicString&, bool force, ExceptionState&);
-  void replace(const AtomicString& token,
+  bool replace(const AtomicString& token,
                const AtomicString& new_token,
                ExceptionState&);
   bool supports(const AtomicString&, ExceptionState&);

third_party/WebKit/Source/core/dom/DOMTokenList.idl

@@ -34,7 +34,7 @@
     [RaisesException, CEReactions, CustomElementCallbacks] void add(DOMString... tokens);
     [RaisesException, CEReactions, CustomElementCallbacks] void remove(DOMString... tokens);
     [RaisesException, CEReactions, CustomElementCallbacks] boolean toggle(DOMString token, optional boolean force);
-    [RaisesException, CEReactions] void replace(DOMString token, DOMString newToken);
+    [RaisesException, CEReactions] boolean replace(DOMString token, DOMString newToken);
     [RaisesException, CustomElementCallbacks] boolean supports(DOMString token);
     [CEReactions] attribute DOMString value;
     stringifier;