Introduce CustomElementRegistry#get() method

third_party/WebKit/Source/core/dom/custom/CustomElementDefinition.h

Index: third_party/WebKit/Source/core/dom/custom/CustomElementDefinition.h
diff --git a/third_party/WebKit/Source/core/dom/custom/CustomElementDefinition.h b/third_party/WebKit/Source/core/dom/custom/CustomElementDefinition.h
index e410349ac24f66484daacbb7c199e68be1822b60..aca75ab78d0e92d763993d0224175795b5b30c6b 100644
--- a/third_party/WebKit/Source/core/dom/custom/CustomElementDefinition.h
+++ b/third_party/WebKit/Source/core/dom/custom/CustomElementDefinition.h
@@ -5,6 +5,7 @@
 #ifndef CustomElementDefinition_h
 #define CustomElementDefinition_h
 
+#include "bindings/core/v8/ScriptValue.h"
 #include "core/CoreExport.h"
 #include "core/dom/custom/CustomElementDescriptor.h"
 #include "platform/heap/Handle.h"
@@ -12,6 +13,8 @@
 
 namespace blink {
 
+class ScriptState;
+
 class CORE_EXPORT CustomElementDefinition
     : public GarbageCollectedFinalized<CustomElementDefinition> {
     WTF_MAKE_NONCOPYABLE(CustomElementDefinition);
@@ -21,6 +24,13 @@ public:
 
     const CustomElementDescriptor& descriptor() { return m_descriptor; }
 
+    // TODO(yosin): To support Web Module, once we introduce abstract class
+    // |CustomElementConstructor|, allows us to have JavaScript and C++
+    // constructor, and ask binding layer to convert |CustomElementConstructor|
+    // to |ScriptValue|, we should replace |getConstructorForScript()| by
+    // |getConstructor() -> CustomElementConstructor|.
+    virtual ScriptValue getConstructorForScript() = 0;
+
     DEFINE_INLINE_VIRTUAL_TRACE() { }
 
 private: