Use V8TRYCATCH_FOR_V8STRINGRESOURCE() macro instead of toCoreStringWithUndefinedOrNullCheck()

Source/bindings/v8/custom/V8WindowCustom.cpp

Index: Source/bindings/v8/custom/V8WindowCustom.cpp
diff --git a/Source/bindings/v8/custom/V8WindowCustom.cpp b/Source/bindings/v8/custom/V8WindowCustom.cpp
index af29c16a0551f0f5deb30f4e2ab572e23d049623..2b6106e18603a2f38019d1afd06fba940fb05da4 100644
--- a/Source/bindings/v8/custom/V8WindowCustom.cpp
+++ b/Source/bindings/v8/custom/V8WindowCustom.cpp
@@ -364,10 +364,9 @@ void V8Window::showModalDialogMethodCustom(const v8::FunctionCallbackInfo<v8::Va
         return;
     }
 
-    // FIXME: Handle exceptions properly.
-    String urlString = toCoreStringWithUndefinedOrNullCheck(info[0]);
+    V8TRYCATCH_FOR_V8STRINGRESOURCE_VOID(V8StringResource<WithUndefinedOrNullCheck>, urlString, info[0]);
     DialogHandler handler(info[1]);
-    String dialogFeaturesString = toCoreStringWithUndefinedOrNullCheck(info[2]);
+    V8TRYCATCH_FOR_V8STRINGRESOURCE_VOID(V8StringResource<WithUndefinedOrNullCheck>, dialogFeaturesString, info[2]);
 
     impl->showModalDialog(urlString, dialogFeaturesString, activeDOMWindow(), firstDOMWindow(), setUpDialog, &handler);