[Presentation API] Adding a flag to disable gesture check for starting presentations

third_party/WebKit/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 "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/Settings.h"
 #include "core/frame/UseCounter.h"
 #include "modules/EventTargetModules.h"
 #include "modules/presentation/PresentationAvailability.h"
 #include "modules/presentation/PresentationAvailabilityCallbacks.h"
 #include "modules/presentation/PresentationConnection.h"
 #include "modules/presentation/PresentationConnectionCallbacks.h"
 #include "modules/presentation/PresentationController.h"
 #include "modules/presentation/PresentationError.h"
 #include "platform/UserGestureIndicator.h"
 
 namespace blink {
 
 namespace {
 
 // TODO(mlamouri): refactor in one common place.
 WebPresentationClient* presentationClient(ExecutionContext* executionContext)
 {
     ASSERT(executionContext && executionContext->isDocument());
 
     Document* document = toDocument(executionContext);
     if (!document->frame())
         return nullptr;
     PresentationController* controller = PresentationController::from(*document->frame());
     return controller ? controller->client() : nullptr;
 }
 
+Settings* getSettings(ExecutionContext* executionContext)
+{
+    ASSERT(executionContext && executionContext->isDocument());
+
+    Document* document = toDocument(executionContext);
+    return document->settings();
+}
+
 } // anonymous namespace
 
 // static
 PresentationRequest* PresentationRequest::create(ExecutionContext* executionContext, const String& url, ExceptionState& exceptionState)
 {
     KURL parsedUrl = KURL(executionContext->url(), url);
     if (!parsedUrl.isValid() || parsedUrl.protocolIsAbout()) {
         exceptionState.throwTypeError("'" + url + "' can't be resolved to a valid URL.");
         return nullptr;
     }
@@ skipping 29 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()) {
+    Settings* settings = getSettings(executionContext());

[whywhat, 2016/02/04 20:39:08]

I wonder if this can be null? Does similar code check for Settings being null?

[Zhiqiang Zhang (Slow), 2016/02/05 16:20:33]

See here:
https://code.google.com/p/chromium/codesearch#chromium/src/third_party/WebKit...

The comment says that Document::settings() can be null.

+    bool bypassGestureCheck = settings && settings->presentationRequiresUserGesture();

[whywhat, 2016/02/04 20:39:08]

I think the name of the variable means the opposite to its value.
isUserGestureRequired or something?

[Zhiqiang Zhang (Slow), 2016/02/05 16:20:33]

Done.

+
+    if (!bypassGestureCheck && !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 PresentationConnectionCallbacks(resolver, this));
@@ skipping 41 matching lines @@
     ActiveDOMObject::trace(visitor);
 }
 
 PresentationRequest::PresentationRequest(ExecutionContext* executionContext, const KURL& url)
     : ActiveDOMObject(executionContext)
     , m_url(url)
 {
 }
 
 } // namespace blink