fix: Handle unicode in webview events.

[tdomhan]

The request header does not support unicode characters leading to Type: error when calling setRequestHeader with a non-ascii string. This PR first encodes the data using base64 before setting the header. The downside is that this increases the content size by 33%.

This addresses #3125

Running the build updates all Javascript files. I assume this is due to the Typescript version. I'm using 5.7.2. Let me know if I should be using a specific version.

[jkelleyrtp]

Wow, thanks for the quick fix! Do we need to do base64 encoding? Is there a chance that our mime-type is just not set properly on the XHR request that we can fix by using text/plain;charset=UTF-8 as the mime-type?

[tdomhan]

I'll double check. In my initial attempts I wasn't able to get this work without the base64 workaround, but indeed if this could be avoided that'd be great and I hadn't changed the mime-type yet.

[tdomhan]

I tried setting the mime type to text/plain;charset=UTF-8 but run into the same issue. From what I'm gathering this would only affect the body and the header only allows ISO-8859-1.

[jkelleyrtp]

Ah good point, we had to switch to the header from the body since wry was stripping the body on android. I'll check and see if that's still the case...