`onFileDownload` is called with the URL that you can use to download the file.
When RNCWebView detects that the HTTP response should result in a file download,
`onFileDownload` is called. The client can then provide code to download
the file.
RNCWebView determines that a file download should take place if either of the
following is true:
1. The HTTP response contains a `Content-Disposition` header that is of type
'attachment'
2. The MIME type of the response cannot be rendered by the iOS WebView
* Don't show camera options for a file upload that would result in nothing happening for the user.
On Android, if the application declares the camera permission, then even intents
that use the camera require permission to be granted. This is a problem for apps
that combine an in-app camera with a WebView that has file uploading and the user
has not given permission for the camera.
Note, this will not request permission for camera. This will simply prevent
showing the camera options that would be a no-op action for users. It does this
by checking if the camera permission is declared, and if so, checks that the
user has granted permission.
More information: https://blog.egorand.me/taking-photos-not-so-simply-how-i-got-bitten-by-action_image_capture/
* Add example and documentation about camera option availability in file uploads for Android.
Roman Volosovskyi
Kai Guo
trcoffman
Jamie Birch
Daniel Vicory
Tom Underhill
Jesse Katsumata