feat: Expose setUseWideViewPort on Android (#106999)

[Gustl22]

The option to set whether the webview should use the wide viewport should be available.
Also the default is changed to false, because this is the expected behavior on Android devices:
https://developer.android.com/develop/ui/views/layout/webapps/targeting
On iOS also the default behavior is to NOT use wide viewport, so this is aligned.

Note: When your page is rendered in a WebView, it doesn't use wide viewport mode by default. You can enable wide viewport mode with setUseWideViewPort().

This also partically solves flutter/flutter#106999, as then the correct height is returned from document.documentElement.scrollHeight; property.

If you had to change anything in the flutter/tests repo, include a link to the migration guide as per the breaking change policy.

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[stuartmorgan-g]

Also the default is changed to false, because this is the expected behavior on Android devices

This may break some people; see flutter/flutter#93125 for example.

[Gustl22]

Thank you for the intels.

This may break some people; see flutter/flutter#93125 for example.

That's true, what exactly should be the next steps? I also tried to reproduce your linked issue, but couldn't as the linked site was reworked and doesn't show this problem any more.

1. Use true as default for setUseWideViewPort

• would ensure that nothing breaks due to keeping the current default
• may leads to annoyance as package users expect the same behavior on Android and iOS

2. Use false as default for setUseWideViewPort

• Making a breaking change and write a migration guide
• probably very few care as the behavior was different on Android and iOS and noone noticed
• Nontheless could lead to unexpected outcome for certain products, when using flutter specifically on only one platform
• WebViews are hard to test so the behavior should be aligned in both platforms to not challenge more differences across both platforms
• Raise a major version for webview package
• Aligns with native Android and Flutter iOS implementation

Webkit / iOS	Android setUseWideViewPort(true)	Android setUseWideViewPort(false)