Revert "Remove OwnPtr from Blink."

third_party/WebKit/Source/wtf/HashTraits.h

Index: third_party/WebKit/Source/wtf/HashTraits.h
diff --git a/third_party/WebKit/Source/wtf/HashTraits.h b/third_party/WebKit/Source/wtf/HashTraits.h
index 3ddd834e2995c00ef327ecec85f9cbbfb1d55ffe..bd8f8c9d7bc9e8c40d21d46fb4b5017a4737b31c 100644
--- a/third_party/WebKit/Source/wtf/HashTraits.h
+++ b/third_party/WebKit/Source/wtf/HashTraits.h
@@ -155,6 +155,23 @@ template <typename T> struct SimpleClassHashTraits : GenericHashTraits<T> {
     static bool isDeletedValue(const T& value) { return value.isHashTableDeletedValue(); }
 };
 
+template <typename P> struct HashTraits<OwnPtr<P>> : SimpleClassHashTraits<OwnPtr<P>> {
+    typedef std::nullptr_t EmptyValueType;
+
+    static EmptyValueType emptyValue() { return nullptr; }
+
+    static const bool hasIsEmptyValueFunction = true;
+    static bool isEmptyValue(const OwnPtr<P>& value) { return !value; }
+
+    typedef typename OwnPtr<P>::PtrType PeekInType;
+
+    static void store(PassOwnPtr<P> value, OwnPtr<P>& storage) { storage = std::move(value); }
+
+    typedef typename OwnPtr<P>::PtrType PeekOutType;
+    static PeekOutType peek(const OwnPtr<P>& value) { return value.get(); }
+    static PeekOutType peek(std::nullptr_t) { return 0; }
+};
+
 template <typename P> struct HashTraits<RefPtr<P>> : SimpleClassHashTraits<RefPtr<P>> {
     typedef std::nullptr_t EmptyValueType;
     static EmptyValueType emptyValue() { return nullptr; }