Make BeforeInstallPromptEvent cancelable

third_party/WebKit/Source/modules/app_banner/BeforeInstallPromptEvent.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/app_banner/BeforeInstallPromptEvent.h"
 
 #include "core/dom/DOMException.h"
 #include "core/dom/Document.h"
 #include "core/dom/ExceptionCode.h"
 #include "core/frame/UseCounter.h"
@@ skipping 16 matching lines @@
                                           UserChoiceProperty::UserChoice)),
       m_promptCalled(false) {
   DCHECK(m_bannerService);
   DCHECK(m_binding.is_bound());
   UseCounter::count(&frame, UseCounter::BeforeInstallPromptEvent);
 }
 
 BeforeInstallPromptEvent::BeforeInstallPromptEvent(
     const AtomicString& name,
     const BeforeInstallPromptEventInit& init)
-    : Event(name, false, true), m_binding(this), m_promptCalled(false) {
+    : Event(name, init), m_binding(this), m_promptCalled(false) {
   if (init.hasPlatforms())
     m_platforms = init.platforms();
 }
 
 BeforeInstallPromptEvent::~BeforeInstallPromptEvent() {}
 
 void BeforeInstallPromptEvent::dispose() {
   m_bannerService.reset();
   m_binding.Close();
 }
 
 Vector<String> BeforeInstallPromptEvent::platforms() const {
   return m_platforms;
 }
 
 ScriptPromise BeforeInstallPromptEvent::userChoice(ScriptState* scriptState) {
   UseCounter::count(scriptState->getExecutionContext(),
                     UseCounter::BeforeInstallPromptEventUserChoice);
   // |m_binding| must be bound to allow the AppBannerService to resolve the
   // userChoice promise.
   if (m_userChoice && m_binding.is_bound())
     return m_userChoice->promise(scriptState->world());
   return ScriptPromise::rejectWithDOMException(
       scriptState,
-      DOMException::create(InvalidStateError,
+      DOMException::create(NotAllowedError,

[Matt Giuca, 2017/04/26 05:28:50]

This is technically a breaking change (though NOBODY should be relying on it).

I've sent an email to the team asking whether we can make such a change without
an Intent email.

[Matt Giuca, 2017/05/11 01:42:05]

Per https://crbug.com/658639, this bug was a mistake (it was originally speced
as InvalidStateError) so you can remove this change.

Actually the spec no longer calls for ANY exception here. I've asked if it's a
mistake on https://github.com/w3c/manifest/issues/577, but in the mean time,
let's just keep the Chrome behaviour as-is.

This means you should update the CL description to not mention changing the
exception type, and remove the reference to bug 658639.

[dominickn, 2017/05/11 01:51:57]

Done.

                            "userChoice cannot be accessed on this event."));
 }
 
 ScriptPromise BeforeInstallPromptEvent::prompt(ScriptState* scriptState) {
   // |m_bannerService| must be bound to allow us to inform the AppBannerService
   // to display the banner now.
   if (!defaultPrevented() || m_promptCalled || !m_bannerService.is_bound()) {
     return ScriptPromise::rejectWithDOMException(
         scriptState,
-        DOMException::create(InvalidStateError,
+        DOMException::create(NotAllowedError,
                              "The prompt() method may only be called once, "
                              "following preventDefault()."));
   }
 
   UseCounter::count(scriptState->getExecutionContext(),
                     UseCounter::BeforeInstallPromptEventPrompt);
 
   m_promptCalled = true;
   m_bannerService->DisplayAppBanner();
   return ScriptPromise::castUndefined(scriptState);
@@ skipping 20 matching lines @@
   m_userChoice->resolve(AppBannerPromptResult::create(
       emptyAtom, AppBannerPromptResult::Outcome::Dismissed));
 }
 
 DEFINE_TRACE(BeforeInstallPromptEvent) {
   visitor->trace(m_userChoice);
   Event::trace(visitor);
 }
 
 }  // namespace blink