[pointer_interceptor] Remove iOS and Android from example

[stuartmorgan-g]

The package is web-only, and the example doesn't build for other platforms,
so it shouldn't be configured for them.

This may be a point of user confusion, but it also fails if we fix the
repo script to build example apps (which it currently isn't, I believe
due to a long-ago regression that hadn't been noticed).

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[ditman]

The package is web-only, and doesn't build for other platforms

The package is only active in the web, but it should compile (and noop) in mobile platforms (see the conditional export here)

I remember running the example app on Android a while back, but maybe it has bit rotted since then? :S

[stuartmorgan-g]

Hm, I'll take another look. IIRC it was complaining about dart:html when I ran flutter/plugins#4248 locally.

[ditman]

Hm, I'll take another look. IIRC it was complaining about dart:html when I ran flutter/plugins#4248 locally.

Thanks for taking another look, I might have screwed up the example since I've written it... or maybe its integration tests :S

[stuartmorgan-g]

lib/main.dart:6:8: Error: Not found: 'dart:html'
import 'dart:html' as html;
       ^
lib/main.dart:18:1: Error: Type 'html.Element' not found.
html.Element htmlElement = html.DivElement()
^^^^^^^^^^^^
lib/main.dart:18:6: Error: 'Element' isn't a type.
html.Element htmlElement = html.DivElement()
     ^^^^^^^
lib/main.dart:18:33: Error: Method not found: 'DivElement'.
html.Element htmlElement = html.DivElement()
                                ^^^^^^^^^^
lib/main.dart:204:18: Error: Constant evaluation error:
    return const HtmlElementView(
                 ^
../../../../flutter/packages/flutter/lib/src/widgets/platform_view.dart:350:15: Context: This assertion failed with message: HtmlElementView is only available on Flutter Web.
       assert(kIsWeb, 'HtmlElementView is only available on Flutter Web.'),

see the conditional export here

That's not the problem, this is

I remember running the example app on Android a while back, but maybe it has bit rotted since then? :S

That line dates back to #256 so I'm not sure how you could ever have run the example on anything but web.

So do you want to rewrite the example, or move forward with this PR?

[ditman]

Gosh, you're right, that's bad...

So do you want to rewrite the example, or move forward with this PR?

Nah, let's move on with the PR and I'll look at adding an Android version later, since I need to reshuffle a bunch of code to make it work :/