bluetooth: Disconnect if the page becomes hidden or is closed.

third_party/WebKit/Source/modules/bluetooth/BluetoothGATTRemoteServer.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 BluetoothGATTRemoteServer_h
 #define BluetoothGATTRemoteServer_h
 
 #include "bindings/core/v8/ScriptWrappable.h"
 #include "bindings/modules/v8/UnionTypesModules.h"
+#include "core/dom/ActiveDOMObject.h"
+#include "core/page/PageLifecycleObserver.h"
 #include "platform/heap/Heap.h"
 #include "public/platform/modules/bluetooth/WebBluetoothGATTRemoteServer.h"
 #include "wtf/OwnPtr.h"
 #include "wtf/PassOwnPtr.h"
 #include "wtf/text/WTFString.h"
 
 namespace blink {
 
 class ScriptPromise;
 class ScriptPromiseResolver;
 class ScriptState;
 
 // BluetoothGATTRemoteServer provides a way to interact with a connected bluetooth peripheral.
 //
 // Callbacks providing WebBluetoothGATTRemoteServer objects are handled by
 // CallbackPromiseAdapter templatized with this class. See this class's
 // "Interface required by CallbackPromiseAdapter" section and the
 // CallbackPromiseAdapter class comments.
 class BluetoothGATTRemoteServer final
     : public GarbageCollectedFinalized<BluetoothGATTRemoteServer>
+    , public ActiveDOMObject
+    , public PageLifecycleObserver
     , public ScriptWrappable {
+    USING_PRE_FINALIZER(BluetoothGATTRemoteServer, dispose);
     DEFINE_WRAPPERTYPEINFO();
+    WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(BluetoothGATTRemoteServer);
 public:
-    BluetoothGATTRemoteServer(PassOwnPtr<WebBluetoothGATTRemoteServer>);
+    BluetoothGATTRemoteServer(ExecutionContext*, PassOwnPtr<WebBluetoothGATTRemoteServer>);
 
     // Interface required by CallbackPromiseAdapter:
     using WebType = OwnPtr<WebBluetoothGATTRemoteServer>;
     static BluetoothGATTRemoteServer* take(ScriptPromiseResolver*, PassOwnPtr<WebBluetoothGATTRemoteServer>);
 
+    // We should disconnect from the device in all of the following cases:
+    // 1. When the object gets GarbageCollected e.g. it went out of scope.

[Jeffrey Yasskin, 2016/01/21 23:44:33]

We should allow folks to turn on notifications, listen for events on
navigator.bluetooth, and then drop the BluetoothGATTRemoteServer and the
BluetoothDevice, without getting disconnected. Maybe not yet, since we don't
have event bubbling, but could you add a TODO for that and link to
https://crbug.com/570083?

[ortuno, 2016/01/22 21:34:12]

Done.

+    // dispose() is called in this case.
+    // 2. When the parent document gets detached e.g. reloading a page.
+    // stop() is called in this case.
+    // 3. When the tab is no longer in the foreground e.g. change tabs.

[Jeffrey Yasskin, 2016/01/21 23:44:33]

I'd phrase this something like "For now (https://crbug.com/579746), when the tab
is no longer ..." so it's clear from the start that this isn't part of the
long-term behavior.

[ortuno, 2016/01/22 21:34:12]

Done.

+    // pageVisibilityChanged() is called in this case.
+    // TODO(ortuno): Allow connections when the tab is in the background.
+    // This is a short term solution instead of implementing a tab indicator
+    // for bluetooth connections.
+    // https://crbug.com/579746
+
+    // USING_PRE_FINALIZER interface.
+    // Called before the object gets garbage collected.
+    void dispose();
+
+    // ActiveDOMObject interface.
+    void stop() override;
+
+    // PageLifecycleObserver interface.
+    void pageVisibilityChanged() override;
+
+    void disconnectIfConnected();
+
     // Interface required by Garbage Collectoin:
-    DEFINE_INLINE_TRACE() { }
+    DECLARE_VIRTUAL_TRACE();
 
     // IDL exposed interface:
     bool connected() { return m_webGATT->connected; }
     void disconnect(ScriptState*);
     ScriptPromise getPrimaryService(ScriptState*, const StringOrUnsignedLong& service, ExceptionState&);
 
 private:
     OwnPtr<WebBluetoothGATTRemoteServer> m_webGATT;
 };
 
 } // namespace blink
 
 #endif // BluetoothDevice_h