[web] Fix obsolete meta-tag "apple-mobile-web-app-capable". #154596
Description
The default project template of Flutter web, adds the following meta-tag:
<meta name="apple-mobile-web-app-capable" content="yes">But that seems to have been deprecated since iOS 8 days (maybe earlier?)
Chrome is now nagging about this with the following warning:
Warning
<meta name="apple-mobile-web-app-capable" content="yes"> is deprecated. Please include <meta name="mobile-web-app-capable" content="yes">
We should do as Chrome says!
Some recent comments about apple-mobile-web-app-capable and friends:
Caution
Warning: Before the web app manifest spec was defined, several browsers, including Safari on iOS/iPadOS and Chrome on Android, supported custom <meta> elements to describe the application experience, such as apple-mobile-web-app-capable. Do not use these <meta> elements today; it's no longer recommended, and may harm the installation experience when the browser can't load the manifest properly; the experience you get as a fallback may be different and unexpected. Source.
Caution
Warning: If Safari can't load the manifest, it will fall back to check if your PWA has some deprecated meta tags, such as apple-mobile-web-app-capable. You should not use these metatags. They provide a home screen app experience without essential attributes for your PWA, such as honoring the start_url or the scope attributes, making a terrible app experience. Source.