[url_launcher_ios] Fix test button text to work on iOS 26 (#9766)

Handle either a "Done" (iOS 18) or a "Close" (iOS 26) button:

iOS 26 simulator:
<img width="406" height="575" alt="Screenshot 2025-08-13 at 3 45 02 PM" src="https://github.com/user-attachments/assets/5c7460f1-626c-404b-9de4-0827e34cd910" />

Remove validation of UI elements (`ForwardButton`, `Share`) that the plugin doesn't control.
Fixes flutter/flutter#173100

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Author: jmagman

packages/url_launcher/url_launcher_ios/CHANGELOG.md

@@ -1,3 +1,7 @@
+## NEXT
+
+* Fixes integration test button text matcher to work on iOS 26.
+
 ## 6.3.4
 
 * Updates to Pigeon 25.5.0.

packages/url_launcher/url_launcher_ios/example/ios/RunnerUITests/URLLauncherUITests.swift

@@ -28,10 +28,11 @@ class URLLauncherUITests: XCTestCase {
       button.tap()
       let webView = app.webViews.firstMatch
       XCTAssertTrue(webView.waitForExistence(timeout: 30.0))
-      XCTAssertTrue(app.buttons["ForwardButton"].waitForExistence(timeout: 30.0))
-      XCTAssertTrue(app.buttons["Share"].exists)
-      XCTAssertTrue(app.buttons["OpenInSafariButton"].exists)
-      let doneButton = app.buttons["Done"]
+      XCTAssertTrue(app.buttons["OpenInSafariButton"].waitForExistence(timeout: 30.0))
+
+      // iOS 18 is "Done". iOS 26 is "Close".
+      let doneButtonPredicate = NSPredicate(format: "label = 'Close' OR label = 'Done'")
+      let doneButton = app.buttons.element(matching: doneButtonPredicate).firstMatch
       XCTAssertTrue(doneButton.waitForExistence(timeout: 30.0))
       // This should just be doneButton.tap, but for some reason that stopped working in Xcode 15;
       // tapping via coordinate works, however.