Require UIViewController for presentation in getOAuthToken

This is a step towards no longer requiring `NewGoogleAuthenticator` to
store the `contextProvider`.

Author: mokagio

Demo/AuthenticatorDemo/ViewController+WordPressAuthenticator.swift

@@ -87,7 +87,7 @@ extension ViewController {
     func getAuthTokenFromGoogle() {
         Task { @MainActor in
             do {
-                let token = try await self.googleAuthenticator.getOAuthToken()
+                let token = try await self.googleAuthenticator.getOAuthToken(from: self)
 
                 presentAlert(
                     title: "🎉",

WordPressAuthenticator/GoogleSignIn/NewGoogleAuthenticator.swift

@@ -56,9 +56,28 @@ public class NewGoogleAuthenticator: NSObject {
     }
 
     /// Get the user's OAuth token from their Google account. This token can be used to authenticate with the WordPress backend.
-    public func getOAuthToken() async throws -> IDToken {
+    ///
+    /// The app will present the browser to hand over authentication to Google from the given `UIViewController`.
+    public func getOAuthToken(from viewController: UIViewController) async throws -> IDToken {
+        return try await getOAuthToken(
+            from: WebAuthenticationPresentationContext(viewController: viewController)
+        )
+    }
+
+    /// Get the user's OAuth token from their Google account. This token can be used to authenticate with the WordPress backend.
+    ///
+    /// The app will present the browser to hand over authentication to Google using the given
+    /// `ASWebAuthenticationPresentationContextProviding`.
+    public func getOAuthToken(
+        from contextProvider: ASWebAuthenticationPresentationContextProviding
+    ) async throws -> IDToken {
         let pkce = try ProofKeyForCodeExchange()
-        let url = try await getURL(clientId: clientId, scheme: scheme, pkce: pkce, contextProvider: contextProvider)
+        let url = try await getURL(
+            clientId: clientId,
+            scheme: scheme,
+            pkce: pkce,
+            contextProvider: contextProvider
+        )
         return try await requestOAuthToken(url: url, clientId: clientId, audience: audience, pkce: pkce)
     }
 

WordPressAuthenticator/Unified Auth/GoogleAuthenticator.swift

@@ -319,7 +319,7 @@ extension GoogleAuthenticator {
         )
 
         await SVProgressHUD.show()
-        return try await sdkLessGoogleAuthenticator.getOAuthToken()
+        return try await sdkLessGoogleAuthenticator.getOAuthToken(from: viewController)
     }
 }