[webnfc] Implement nfc.watch in blink nfc module.

third_party/WebKit/Source/modules/nfc/NFC.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef NFC_h
 #define NFC_h
 
 #include "bindings/core/v8/ScriptPromise.h"
 #include "bindings/core/v8/ScriptWrappable.h"
 #include "bindings/modules/v8/StringOrArrayBufferOrNFCMessage.h"
 #include "core/dom/ContextLifecycleObserver.h"
 #include "core/page/PageVisibilityObserver.h"
 #include "device/nfc/nfc.mojom-blink.h"
+#include "modules/nfc/MessageCallback.h"
 #include "mojo/public/cpp/bindings/binding.h"
+#include "wtf/HashMap.h"
 
 namespace blink {
 
 class MessageCallback;
 class NFCError;
 class NFCPushOptions;
 using NFCPushMessage = StringOrArrayBufferOrNFCMessage;
 class NFCWatchOptions;
 
 class NFC final : public GarbageCollectedFinalized<NFC>,
@@ skipping 32 matching lines @@
   // Cancels all watch operations.
   ScriptPromise cancelWatch(ScriptState*);
 
   // Implementation of PageVisibilityObserver.
   void pageVisibilityChanged() override;
 
   // Interface required by garbage collection.
   DECLARE_VIRTUAL_TRACE();
 
  private:
+  // Returns promise with DOMException if feature is not supported
+  // or when context is not secure. Otherwise, returns empty promise.
+  ScriptPromise rejectIfNotSupported(ScriptState*);
+
   void OnRequestCompleted(ScriptPromiseResolver*,
                           device::nfc::mojom::blink::NFCErrorPtr);
   void OnConnectionError();
+  void OnWatchRegistered(MessageCallback*,
+                         ScriptPromiseResolver*,
+                         uint32_t id,
+                         device::nfc::mojom::blink::NFCErrorPtr);
 
   // device::nfc::mojom::blink::NFCClient implementation.
   void OnWatch(const WTF::Vector<uint32_t>& ids,
                device::nfc::mojom::blink::NFCMessagePtr) override;
 
  private:
   explicit NFC(LocalFrame*);
   device::nfc::mojom::blink::NFCPtr m_nfc;
   mojo::Binding<device::nfc::mojom::blink::NFCClient> m_client;
   HeapHashSet<Member<ScriptPromiseResolver>> m_requests;
+  using WatchCallbacksMap = HeapHashMap<uint32_t, Member<MessageCallback>>;
+  WatchCallbacksMap m_callbacks;
 };
 
 }  // namespace blink
 
 #endif  // NFC_h