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

third_party/WebKit/Source/modules/bluetooth/BluetoothGATTRemoteServer.cpp

 // 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.
 
 #include "modules/bluetooth/BluetoothGATTRemoteServer.h"
 
 #include "bindings/core/v8/CallbackPromiseAdapter.h"
 #include "bindings/core/v8/ScriptPromise.h"
 #include "bindings/core/v8/ScriptPromiseResolver.h"
 #include "core/dom/DOMException.h"
+#include "core/dom/Document.h"
 #include "core/dom/ExceptionCode.h"
 #include "modules/bluetooth/BluetoothError.h"
 #include "modules/bluetooth/BluetoothGATTService.h"
 #include "modules/bluetooth/BluetoothSupplement.h"
 #include "modules/bluetooth/BluetoothUUID.h"
 #include "public/platform/modules/bluetooth/WebBluetooth.h"
 #include "wtf/OwnPtr.h"
 
 namespace blink {
-
-BluetoothGATTRemoteServer::BluetoothGATTRemoteServer(PassOwnPtr<WebBluetoothGATTRemoteServer> webGATT)
-    : m_webGATT(webGATT)
+namespace {
+bool isPageVisible(Page* page)

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

Add a blank line after "namespace {". (Ditto from the other anonymous namespace
blank line comment.)

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

Done.

 {
+    return page->visibilityState() == PageVisibilityStateVisible;
 }
 
-BluetoothGATTRemoteServer* BluetoothGATTRemoteServer::take(ScriptPromiseResolver*, PassOwnPtr<WebBluetoothGATTRemoteServer> webGATT)
+} // namespace
+BluetoothGATTRemoteServer::BluetoothGATTRemoteServer(ExecutionContext* context, PassOwnPtr<WebBluetoothGATTRemoteServer> webGATT)
+    : ActiveDOMObject(context)
+    , PageLifecycleObserver(toDocument(context)->page())
+    , m_webGATT(webGATT)
+{
+    // See example in Source/platform/heap/ThreadState.h
+    ThreadState::current()->registerPreFinalizer(this);
+}
+
+BluetoothGATTRemoteServer* BluetoothGATTRemoteServer::take(ScriptPromiseResolver* resolver, PassOwnPtr<WebBluetoothGATTRemoteServer> webGATT)
 {
     ASSERT(webGATT);
-    return new BluetoothGATTRemoteServer(webGATT);
+    BluetoothGATTRemoteServer* server = new BluetoothGATTRemoteServer(resolver->executionContext(), webGATT);
+    if (!isPageVisible(server->page())) {
+        server->disconnectIfConnected();
+    }
+    server->suspendIfNeeded();
+    return server;
+}
+
+void BluetoothGATTRemoteServer::dispose()
+{
+    disconnectIfConnected();
+}
+
+void BluetoothGATTRemoteServer::stop()
+{
+    disconnectIfConnected();
+}
+
+void BluetoothGATTRemoteServer::pageVisibilityChanged()
+{
+    if (!isPageVisible(page())) {
+        disconnectIfConnected();
+    }
+}
+
+void BluetoothGATTRemoteServer::disconnectIfConnected()
+{
+    if (m_webGATT->connected) {
+        m_webGATT->connected = false;

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

FWIW (not for this CL), I'm uncomfortable having 'connected' represented as a
boolean that we have to manually keep in sync with the actual connected state.
If you ever see a way to calculate it from something else, perhaps an object
that represents the connection itself, let's switch to that.

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

I agree. I think things will become clearer once we resolve the spec issues
regarding connection/disconnection. For now this just respects what the spec
says.

+        WebBluetooth* webbluetooth = BluetoothSupplement::fromExecutionContext(executionContext());
+        webbluetooth->disconnect(m_webGATT->deviceId);
+    }
+}
+
+DEFINE_TRACE(BluetoothGATTRemoteServer)
+{
+    ActiveDOMObject::trace(visitor);
+    PageLifecycleObserver::trace(visitor);
 }
 
 void BluetoothGATTRemoteServer::disconnect(ScriptState* scriptState)
 {
     m_webGATT->connected = false;
     WebBluetooth* webbluetooth = BluetoothSupplement::fromScriptState(scriptState);
     webbluetooth->disconnect(m_webGATT->deviceId);
 }
 
 ScriptPromise BluetoothGATTRemoteServer::getPrimaryService(ScriptState* scriptState, const StringOrUnsignedLong& service, ExceptionState& exceptionState)
 {
     WebBluetooth* webbluetooth = BluetoothSupplement::fromScriptState(scriptState);
 
     String serviceUUID = BluetoothUUID::getService(service, exceptionState);
     if (exceptionState.hadException())
         return exceptionState.reject(scriptState);
 
     ScriptPromiseResolver* resolver = ScriptPromiseResolver::create(scriptState);
     ScriptPromise promise = resolver->promise();
     webbluetooth->getPrimaryService(m_webGATT->deviceId, serviceUUID, new CallbackPromiseAdapter<BluetoothGATTService, BluetoothError>(resolver));
 
     return promise;
 }
 
 } // namespace blink