Revert of Remove scoped styles.

Source/core/testing/Internals.cpp

Index: Source/core/testing/Internals.cpp
diff --git a/Source/core/testing/Internals.cpp b/Source/core/testing/Internals.cpp
index e66a6786d4cb8c63146c1b432b2cfe654be56c15..58ae5411fb34bc30aa723a12ad376b036497acfe 100644
--- a/Source/core/testing/Internals.cpp
+++ b/Source/core/testing/Internals.cpp
@@ -573,6 +573,15 @@
     return representation;
 }
 
+size_t Internals::numberOfScopedHTMLStyleChildren(const Node* scope, ExceptionState& exceptionState) const
+{
+    if (scope && (scope->isElementNode() || scope->isShadowRoot()))
+        return scope->numberOfScopedHTMLStyleChildren();
+
+    exceptionState.throwDOMException(InvalidAccessError, ExceptionMessages::argumentNullOrIncorrectType(1, "Node"));
+    return 0;
+}
+
 PassRefPtrWillBeRawPtr<CSSComputedStyleDeclaration> Internals::computedStyleIncludingVisitedInfo(Node* node, ExceptionState& exceptionState) const
 {
     if (!node) {