Update UsageCounter methods to be callable on Frames.

Source/bindings/core/v8/custom/V8WindowCustom.cpp

Index: Source/bindings/core/v8/custom/V8WindowCustom.cpp
diff --git a/Source/bindings/core/v8/custom/V8WindowCustom.cpp b/Source/bindings/core/v8/custom/V8WindowCustom.cpp
index b0a945f5f24a56d81d984a29cc6ba46b2ab83294..2e31a7c35eafbedb9d9607464953244f8fb9ab76 100644
--- a/Source/bindings/core/v8/custom/V8WindowCustom.cpp
+++ b/Source/bindings/core/v8/custom/V8WindowCustom.cpp
@@ -247,7 +247,7 @@ void V8Window::postMessageMethodCustom(const v8::FunctionCallbackInfo<v8::Value>
     LocalDOMWindow* source = callingDOMWindow(info.GetIsolate());
 
     ASSERT(window);
-    UseCounter::countIfNotPrivateScript(info.GetIsolate(), window->document(), UseCounter::WindowPostMessage);
+    UseCounter::countIfNotPrivateScript(info.GetIsolate(), window->frame(), UseCounter::WindowPostMessage);
 
     ExceptionState exceptionState(ExceptionState::ExecutionContext, "postMessage", "Window", info.Holder(), info.GetIsolate());
 
@@ -270,7 +270,7 @@ void V8Window::postMessageMethodCustom(const v8::FunctionCallbackInfo<v8::Value>
     if (info.Length() > 2) {
         int transferablesArgIndex = 2;
         if (isLegacyTargetOriginDesignation(info[2])) {
-            UseCounter::countIfNotPrivateScript(info.GetIsolate(), window->document(), UseCounter::WindowPostMessageWithLegacyTargetOriginArgument);
+            UseCounter::countIfNotPrivateScript(info.GetIsolate(), window->frame(), UseCounter::WindowPostMessageWithLegacyTargetOriginArgument);
             targetOriginArgIndex = 2;
             transferablesArgIndex = 1;
         }