Presentation API: PresentationRequest.start() requires user gesture.

Source/modules/presentation/PresentationRequest.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 "config.h"
 #include "modules/presentation/PresentationRequest.h"
 
 #include "bindings/core/v8/CallbackPromiseAdapter.h"
 #include "bindings/core/v8/ExceptionState.h"
 #include "bindings/core/v8/ScriptPromise.h"
 #include "bindings/core/v8/ScriptPromiseResolver.h"
 #include "core/dom/Document.h"
 #include "core/dom/ExecutionContext.h"
 #include "core/frame/UseCounter.h"
 #include "modules/EventTargetModules.h"
 #include "modules/presentation/PresentationAvailability.h"
 #include "modules/presentation/PresentationAvailabilityCallbacks.h"
 #include "modules/presentation/PresentationController.h"
 #include "modules/presentation/PresentationError.h"
 #include "modules/presentation/PresentationSession.h"
 #include "modules/presentation/PresentationSessionCallbacks.h"
+#include "platform/UserGestureIndicator.h"
 
 namespace blink {
 
 namespace {
 
 // TODO(mlamouri): refactor in one common place.
 WebPresentationClient* presentationClient(ExecutionContext* executionContext)
 {
     ASSERT(executionContext && executionContext->isDocument());
 
@@ skipping 43 matching lines @@
     // Prevents garbage collecting of this object when not hold by another
     // object but still has listeners registered.
     return hasEventListeners();
 }
 
 ScriptPromise PresentationRequest::start(ScriptState* scriptState)
 {
     ScriptPromiseResolver* resolver = ScriptPromiseResolver::create(scriptState);
     ScriptPromise promise = resolver->promise();
 
+    if (!UserGestureIndicator::processingUserGesture()) {
+        resolver->reject(DOMException::create(InvalidAccessError, "PresentationRequest::start() requires user gesture."));
+        return promise;
+    }
+
     WebPresentationClient* client = presentationClient(executionContext());
     if (!client) {
         resolver->reject(DOMException::create(InvalidStateError, "The PresentationRequest is no longer associated to a frame."));
         return promise;
     }
     client->startSession(m_url.string(), new PresentationSessionCallbacks(resolver, this));
 
     return promise;
 }
 
@@ skipping 37 matching lines @@
     ActiveDOMObject::trace(visitor);
 }
 
 PresentationRequest::PresentationRequest(ExecutionContext* executionContext, const KURL& url)
     : ActiveDOMObject(executionContext)
     , m_url(url)
 {
 }
 
 } // namespace blink