Add WebSocket unittests.

Source/modules/websockets/WebSocket.h

Index: Source/modules/websockets/WebSocket.h
diff --git a/Source/modules/websockets/WebSocket.h b/Source/modules/websockets/WebSocket.h
index f48c0b52c105b1372df80e3e0d47200ecb617a9b..29081cff2f30e9248cda33353fcc87d38c0f6b93 100644
--- a/Source/modules/websockets/WebSocket.h
+++ b/Source/modules/websockets/WebSocket.h
@@ -51,7 +51,7 @@ namespace WebCore {
 class Blob;
 class ExceptionState;
 
-class WebSocket FINAL : public RefCountedWillBeRefCountedGarbageCollected<WebSocket>, public ScriptWrappable, public EventTargetWithInlineData, public ActiveDOMObject, public WebSocketChannelClient {
+class WebSocket : public RefCountedWillBeRefCountedGarbageCollected<WebSocket>, public ScriptWrappable, public EventTargetWithInlineData, public ActiveDOMObject, public WebSocketChannelClient {
     DEFINE_EVENT_TARGET_REFCOUNTING(RefCountedWillBeRefCountedGarbageCollected<WebSocket>);
 public:
     static const char* subProtocolSeperator();
@@ -125,6 +125,11 @@ public:
 
     void trace(Visitor*);
 
+    static bool isValidSubprotocolString(const String&);
+
+protected:
+    explicit WebSocket(ExecutionContext*);
+
 private:
     // FIXME: This should inherit WebCore::EventQueue.
     class EventQueue FINAL : public RefCountedWillBeGarbageCollectedFinalized<EventQueue> {
@@ -176,7 +181,11 @@ private:
         WebSocketSendTypeMax,
     };
 
-    explicit WebSocket(ExecutionContext*);
+    // This function is virtual for unittests.
+    virtual PassRefPtrWillBeRawPtr<WebSocketChannel> createChannel(ExecutionContext* context, WebSocketChannelClient* client)
+    {
+        return WebSocketChannel::create(context, client);
+    }
 
     // Adds a console message with JSMessageSource and ErrorMessageLevel.
     void logError(const String& message);