[webview_flutter] Support loading data directly in WebView via loadData and loadDataBase64

[philip-peterson]

Description

This PR adds support for loading data directly via the underlying OS's WebView API if possible.

Related Issues

• Fixes Allow loading data to webviews flutter#32827

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[ndusart]

Is there a possibility that this PR can be merged anytime soon ?
From the CI, it seems some incompatibilities with dependencies versions. Could this be fixed with a rebase ?

[philip-peterson]

I never got this feature working unfortunately, and since I'm not writing code for the Flutter ecosystem anymore, this PR is up for grabs to whoever can work on it.

[stuartmorgan-g]

Thanks for the contribution! It sounds from the above like there are no plans to complete this PR, so I'm going to close it. If anyone is interested in moving forward with it, please fork it and submit a new, complete PR.