Updating handling of SSL error in WebView, Fixes AB#3268908

[mohitc1]

Summary:
This PR updates the handling of SSL errors in the Android WebView used for authentication. The change is in response to an incident where the MSA sign-up flow failed due to an expired certificate on an MSA UX web page. The expired certificate was associated with a resource loaded by the page; however, the existing SSL error handling in Common’s WebView would cancel the loading of that resource and subsequently terminate the entire authentication flow. (See PBI for details.)

Solution
Option 1
We simply log and stop loading the resource that caused the error by calling SssHandler.cancel() but not stop the flow by erroring out. This is a simple change. The only thing is the main URL (the url loading in the WebView) itself has SSL error then the flow would end up in blank page. This is as bad as finishing the flow but does not inform calling app of the error via exception.

But if sub-resource has the error, then the flow continues.

This is a low cost solution and easy to implement with slightly poorer UX.

Option 2 (Changes in this PR)
The objective of this update is to improve SSL error handling so that the flow is only cancelled if an SSL error occurs on the main frame resource (the primary page being loaded). If an SSL error affects a sub-resource, only the loading of that specific resource is cancelled, and the overall authentication flow continues. This approach helps prevent unnecessary failures caused by SSL errors on secondary or non-critical resources.

Changes introduced:

1. WebView and WebViewClient Update:

   • Introduces a new AzureActiveDirectoryWebView class, which extends Android's WebView and tracks the active URL being loaded, along with AzureActiveDirectoryWebViewClient
   • Tracking is done by maintaining the next URL (called active url) that's going to be loaded in WebView. We cannot fully rely on WebViewClient's callbacks like onPageStarted because webpage can run into error even before onPageStarted is called. So, we track the URL ourselves by
     1. Setting active Url to be loaded in shouldOverrideUrlLoading(..) callback. This is called before URL is about to get loaded
     2. When WebView's loadUrl is called explicitly. This is case where shouldOverrideUrlLoading() is not called. Since there are multiple places webView.loadUrl is called, added AzureActiveDirectoryWebView which keeps track of the URL being loaded in loadUrl and then continues with webView.loadUrl

2. Handling error in onReceivedSslError

• onReceivedSslError checks if the SSL error is for the main frame (i.e., the main page being loaded). It does so by comparing the active url against the error url on host/domain. If error is for main frame, it cancels the flow and calls the completion callback with an error; otherwise, it just cancels the faulty resource, and let the flow continue.
• For purpose of enabling/disabling new flow, a boolean is added. This should be temporary till changes are stable.

Flighting

3. New SSL Error Handler Toggle:
   • Adds a new intent key (WEB_VIEW_NEW_SSL_ERROR_HANDLER_ENABLED) in AuthenticationConstants.java to control whether the new SSL error handler logic is enabled. This can be used by OneAuth to opt-in or opt-out.
   • Adds a new flight value is well defaulting to true. If the key is not passed. If the key passed, that will be used (primarily meant for OneAuth/MSALCPP). If not, flight would be used (meant for Broker). MSAL would also use default flight value, as there's no remote flighting there.

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