Change beforeinstallprompt event to take an array of platforms.

Source/web/WebLocalFrameImpl.cpp

Index: Source/web/WebLocalFrameImpl.cpp
diff --git a/Source/web/WebLocalFrameImpl.cpp b/Source/web/WebLocalFrameImpl.cpp
index caea872adab0f715961a1a565b5980e79acb49b9..b2c97436aa53c5641081f5a815a7133c7200a8f0 100644
--- a/Source/web/WebLocalFrameImpl.cpp
+++ b/Source/web/WebLocalFrameImpl.cpp
@@ -2030,12 +2030,19 @@ void WebLocalFrameImpl::sendOrientationChangeEvent()
         frame()->localDOMWindow()->sendOrientationChangeEvent();
 }
 
-void WebLocalFrameImpl::willShowInstallBannerPrompt(const WebString& platform, WebAppBannerPromptReply* reply)
+void WebLocalFrameImpl::willShowInstallBannerPrompt(const WebVector<WebString>& platforms, WebAppBannerPromptReply* reply)
 {
     if (!RuntimeEnabledFeatures::appBannerEnabled() || !frame())
         return;
 
-    AppBannerController::willShowInstallBannerPrompt(frame(), platform, reply);
+    AppBannerController::willShowInstallBannerPrompt(frame(), platforms, reply);
+}
+
+
+void WebLocalFrameImpl::willShowInstallBannerPrompt(const WebString& platform, WebAppBannerPromptReply* reply)
+{
+    WebVector<WebString> platforms(&platform, 1);
+    willShowInstallBannerPrompt(platforms, reply);
 }
 
 void WebLocalFrameImpl::requestRunTask(WebSuspendableTask* task) const