Refactor BeforeInstallPromptEvent to use ScriptPromiseProperty

Source/modules/app_banner/BeforeInstallPromptEvent.cpp

Index: Source/modules/app_banner/BeforeInstallPromptEvent.cpp
diff --git a/Source/modules/app_banner/BeforeInstallPromptEvent.cpp b/Source/modules/app_banner/BeforeInstallPromptEvent.cpp
index c4d117dd853329d8168d27b16327fbb5f745a663..2f5c1eeaddd7b1eaa886fee485c3c1879bc7574d 100644
--- a/Source/modules/app_banner/BeforeInstallPromptEvent.cpp
+++ b/Source/modules/app_banner/BeforeInstallPromptEvent.cpp
@@ -5,12 +5,10 @@
 #include "config.h"
 #include "modules/app_banner/BeforeInstallPromptEvent.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/ExceptionCode.h"
-#include "modules/app_banner/AppBannerPromptResult.h"
+#include "modules/app_banner/AppBannerCallbacks.h"
 #include "modules/app_banner/BeforeInstallPromptEventInit.h"
 #include "public/platform/modules/app_banner/WebAppBannerClient.h"
 
@@ -20,12 +18,13 @@ BeforeInstallPromptEvent::BeforeInstallPromptEvent()
 {
 }
 
-BeforeInstallPromptEvent::BeforeInstallPromptEvent(const AtomicString& name, const Vector<String>& platforms, int requestId, WebAppBannerClient* client)
+BeforeInstallPromptEvent::BeforeInstallPromptEvent(const AtomicString& name, ExecutionContext* executionContext, const Vector<String>& platforms, int requestId, WebAppBannerClient* client)
     : Event(name, false, true)
     , m_platforms(platforms)
     , m_requestId(requestId)
     , m_client(client)
-    , m_redispatched(false)
+    , m_userChoice(new UserChoiceProperty(executionContext, this, UserChoiceProperty::UserChoice))
+    , m_registered(false)
 {
 }
 
@@ -33,7 +32,6 @@ BeforeInstallPromptEvent::BeforeInstallPromptEvent(const AtomicString& name, con
     : Event(name, false, true)
     , m_requestId(-1)
     , m_client(nullptr)
-    , m_redispatched(false)
 {
     if (init.hasPlatforms())
         m_platforms = init.platforms();
@@ -50,14 +48,14 @@ Vector<String> BeforeInstallPromptEvent::platforms() const
 
 ScriptPromise BeforeInstallPromptEvent::userChoice(ScriptState* scriptState)
 {
-    if (m_userChoice.isEmpty() && m_client) {
-        ASSERT(m_requestId != -1);
-        RefPtrWillBeRawPtr<ScriptPromiseResolver> resolver = ScriptPromiseResolver::create(scriptState);
-        m_userChoice = resolver->promise();
-        m_client->registerBannerCallbacks(m_requestId, new CallbackPromiseAdapter<AppBannerPromptResult, void>(resolver));
+    if (m_userChoice && m_client && m_requestId != -1) {
+        if (!m_registered) {
+            m_registered = true;
+            m_client->registerBannerCallbacks(m_requestId, new AppBannerCallbacks(m_userChoice.get()));
+        }
+        return m_userChoice->promise(scriptState->world());
     }
-
-    return m_userChoice;
+    return ScriptPromise::rejectWithDOMException(scriptState, DOMException::create(InvalidStateError, "userChoice cannot be accessed on this event."));
 }
 
 const AtomicString& BeforeInstallPromptEvent::interfaceName() const
@@ -67,14 +65,22 @@ const AtomicString& BeforeInstallPromptEvent::interfaceName() const
 
 ScriptPromise BeforeInstallPromptEvent::prompt(ScriptState* scriptState)
 {
-    if (m_client && defaultPrevented() && !m_redispatched) {
-        ASSERT(m_requestId != -1);
-        m_redispatched = true;
-        m_client->showAppBanner(m_requestId);
-        return ScriptPromise::cast(scriptState, v8::Undefined(scriptState->isolate()));
-    }
+    // |m_registered| will be true if userChoice has already been accessed
+    // or prompt() has already been called. Return a rejected promise in both
+    // these cases, as well as if we have a null client or invalid requestId.
+    if (m_registered || !defaultPrevented() || !m_client || m_requestId == -1)
+        return ScriptPromise::rejectWithDOMException(scriptState, DOMException::create(InvalidStateError, "The prompt() method may only be called once, following preventDefault()."));
 
-    return ScriptPromise::rejectWithDOMException(scriptState, DOMException::create(InvalidStateError, "The prompt() method may only be called once, following preventDefault()."));
+    m_registered = true;
+    m_client->registerBannerCallbacks(m_requestId, new AppBannerCallbacks(m_userChoice.get()));
+    m_client->showAppBanner(m_requestId);
+    return ScriptPromise::cast(scriptState, v8::Undefined(scriptState->isolate()));
+}
+
+DEFINE_TRACE(BeforeInstallPromptEvent)
+{
+    visitor->trace(m_userChoice);
+    Event::trace(visitor);
 }
 
 } // namespace blink