bindings: Add C++ versions of WebIDL types and generalize NativeValueTraits.

third_party/WebKit/Source/bindings/tests/results/core/BooleanOrStringOrUnrestrictedDouble.cpp

Index: third_party/WebKit/Source/bindings/tests/results/core/BooleanOrStringOrUnrestrictedDouble.cpp
diff --git a/third_party/WebKit/Source/bindings/tests/results/core/BooleanOrStringOrUnrestrictedDouble.cpp b/third_party/WebKit/Source/bindings/tests/results/core/BooleanOrStringOrUnrestrictedDouble.cpp
index 1aeca9e4bf2f800246d46612cd56ec06928a35e6..64a9da554f988dae20f0e1f29ae60696f030c366 100644
--- a/third_party/WebKit/Source/bindings/tests/results/core/BooleanOrStringOrUnrestrictedDouble.cpp
+++ b/third_party/WebKit/Source/bindings/tests/results/core/BooleanOrStringOrUnrestrictedDouble.cpp
@@ -11,7 +11,9 @@
 // clang-format off
 #include "BooleanOrStringOrUnrestrictedDouble.h"
 
+#include "bindings/core/v8/IDLTypes.h"
 #include "bindings/core/v8/ToV8.h"
+#include "bindings/core/v8/V8BindingForIDLTypes.h"
 
 namespace blink {
 
@@ -88,7 +90,7 @@ void V8BooleanOrStringOrUnrestrictedDouble::toImpl(v8::Isolate* isolate, v8::Loc
   }
 
   if (v8Value->IsNumber()) {
-    double cppValue = toDouble(isolate, v8Value, exceptionState);
+    double cppValue = NativeValueTraits<IDLUnrestrictedDouble>::nativeValue(isolate, v8Value, exceptionState);
     if (exceptionState.hadException())
       return;
     impl.setUnrestrictedDouble(cppValue);