[V3] Add Venmo install check

[richherrera]

Summary of changes

• Add Venmo app install check and pass details to the web SDK

;(function () {
    if (!window.popupBridge) { window.popupBridge = {}; };

    window.popupBridge.getReturnUrlPrefix = function getReturnUrlPrefix() {
        return 'sdk.ios.popup-bridge://popupbridgev1/';
    };
    
    window.popupBridge.isVenmoInstalled = false;
    
    window.popupBridge.open = function open(url) {
        window.webkit.messageHandlers.POPPopupBridge
            .postMessage({
            url: url
        });
    };

    window.popupBridge.sendMessage = function sendMessage(message, data) {
        window.webkit.messageHandlers.POPPopupBridge
            .postMessage({
            message: {
                name: message,
                data: data
            }
        });
    };

    return 0;
})();

README:

Migration guide:

Checklist

• Added a changelog entry

Authors

• @richherrera

[jaxdesmarais]

Can we call this out as a requirement in the README and/or a migration guide if we have one? This check won't work unless merchants register this scheme. Can also add this in the CHANGELOG since it's new functionality.

[richherrera]

Updated, i also attached a couple of screenshots

[jaxdesmarais]

I always find .description a bit of a weird way to represent a string bool. Thoughts on just doing "\(isVenmoInstalled)" here? Take it or leave it, may just be a me problem. :)

[richherrera]

x2, thanks for the feedback, updated: fdbb9db

[jaxdesmarais]

👏