[url_launcher] Update for UIScene compatibility (#10549)
Replaces the code that attempted to find the topmost presented view controller as the context for presenting a Safari view controller with a call to the new registrar API to get the Flutter view's controller.
Since it's now possible for there not to be a view controller, adds an exception for that case. This should only be possible in an add-to-app scenario where someone tries to show an in-app URL from a Flutter view that is not being displayed, which is an unlikely enough scenario that I'm not going to consider this a breaking change.
Fixes https://github.com/flutter/flutter/issues/174415
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[tool] Remove code analysis from podspec-check (#10484)
Replaces the full build-and-analyze version of pod lib lint with the --quick version. This means that this step no longer does native code analysis (which analyze covers), so it no longer needs an exclusion list for packages with warnings.
As a result of this change, flutter/packages no longer has a dependency on the version of Flutter that was published to CocoaPods to facilitate podspec testing.
Fixes https://github.com/flutter/flutter/issues/178806