Make HashTraits<QualifiedName>::emptyValue return a const reference

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

Index: third_party/WebKit/Source/core/dom/QualifiedName.h
diff --git a/third_party/WebKit/Source/core/dom/QualifiedName.h b/third_party/WebKit/Source/core/dom/QualifiedName.h
index 8c6fee54045891b5b072668e9aeeff7ac1c8a32e..c2969784ce8290e2f6924b8bbe5d450cc05d1c73 100644
--- a/third_party/WebKit/Source/core/dom/QualifiedName.h
+++ b/third_party/WebKit/Source/core/dom/QualifiedName.h
@@ -180,6 +180,11 @@ class CORE_EXPORT QualifiedName {
   RefPtr<QualifiedNameImpl> m_impl;
 };
 
+CORE_EXPORT extern const QualifiedName& nullName;
+inline const QualifiedName& QualifiedName::null() {

[sof, 2017/03/07 12:45:33]

I'd prefer to define this 'inplace' with the static decl.

[fs, 2017/03/07 13:30:33]

Done.

+  return nullName;
+}
+
 extern const QualifiedName& anyName;
 inline const QualifiedName& anyQName() {
   return anyName;
@@ -236,7 +241,7 @@ template <>
 struct HashTraits<blink::QualifiedName>
     : SimpleClassHashTraits<blink::QualifiedName> {
   static const bool emptyValueIsZero = false;
-  static blink::QualifiedName emptyValue() {
+  static const blink::QualifiedName& emptyValue() {
     return blink::QualifiedName::null();
   }
 };