tree af8f5c8a4e8b159c5da8610dfb8793fba51d6005
parent 43711d90c99db109e366d04cd30de99d008948e6
author cdumez@apple.com <cdumez@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc> 1571181438 +0000
committer cdumez@apple.com <cdumez@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc> 1571181438 +0000

Webview's drawing area may stay frozen on cross-site back/forward navigation
https://bugs.webkit.org/show_bug.cgi?id=203004

Reviewed by Tim Horton.

Whenever the UIScene becomes foreground / background, the WebPageProxy notifies its currently associated
WebPage in the committed WebProcess so that it can freeze / unfreeze its layer tree with the
BackgroundApplication reason. The issue is that if a WebPage gets suspended on cross-site navigation
(because the UIScene is in the background when the load commits), then the suspended WebPage kept its
a BackgroundApplication freeze. When the UIScene becomes foreground, the WebPage only notifies its
committed page so the suspended page keeps its BackgroundApplication freeze still. If the user now
navigates back, it will restore the suspended WebPage and the view will stay frozen.

To address the issue, we now have the WebPage drop its BackgroundApplication freeze reason, whenever
it transitions from committed to suspended.

* UIProcess/ios/WKApplicationStateTrackingView.mm:
(-[WKApplicationStateTrackingView didMoveToWindow]):
Fix logging, [self isBackground] needs to be called *after* _applicationStateTracker has been
initialized, or it will return YES unconditionally.

* WebProcess/WebPage/WebPage.cpp:
(WebKit::WebPage::setIsSuspended):


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@251166 268f45cc-cd09-0410-ab3c-d52691b4dbfc