[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
@@ skipping 31 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*);

[dcheng, 2016/09/08 04:42:38]

Nit: blink naming convention is still camelCaseWithFirstLetterLowercase. Let's
be consistent with that for the things that aren't implementing mojo methods.

[shalamov, 2016/09/22 13:53:22]

Done.

+
     void OnRequestCompleted(ScriptPromiseResolver*, device::nfc::blink::NFCErrorPtr);
     void OnConnectionError();
+    void OnWatchRegistered(MessageCallback*, ScriptPromiseResolver*, uint32_t id, device::nfc::blink::NFCErrorPtr);
 
     // device::nfc::blink::NFCClient implementation.
     void OnWatch(mojo::WTFArray<uint32_t> ids, device::nfc::blink::NFCMessagePtr) override;
 
 private:
     explicit NFC(LocalFrame*);
     device::nfc::blink::NFCPtr m_nfc;
     mojo::Binding<device::nfc::blink::NFCClient> m_client;
     HeapHashSet<Member<ScriptPromiseResolver>> m_requests;
+    using WatchCallbacksMap = HeapHashMap<uint32_t, Member<MessageCallback>>;
+    WatchCallbacksMap m_callbacks;
 };
 
 } // namespace blink
 
 #endif // NFC_h