Allow stream wrappers not to provide the underlying stream

[jvillafanez]

This is mainly for streams that don't wrap another one, or use a stream not provided by the native fopen function such as smbclient_open

NOTE: This PR targets the release branch.

Description

Provide a way not to provide the source of the stream, otherwise we'd get an annoying log complaining about the missing getSource method in the stream, or we could get real errors if the last stream isn't native.

Related Issue

No opened issue yet.

Motivation and Context

Prevent annoying logs. The flow still works without problems, but the log will keep appearing

How Has This Been Tested?

Manually tested

1. Setup lastest OC master code (10.12.0rc2 - 61a8c68) with the WND app
2. Setup an external storage with the WND app
3. Upload an image to the external storage through ownCloud

The warning log appears.

Note that this PR won't solve the issue by itself. It requires changes in the WND app.
Changes in the app (not core) are expected to be backwards-compatible.

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Database schema changes (next release will require increase of minor version instead of patch)
• Breaking change (fix or feature that would cause existing functionality to change)
• Technical debt
• Tests only (no source changes)

Checklist:

• Code changes
• Unit tests added
• Acceptance tests added
• Documentation ticket raised:
• Changelog item, see TEMPLATE

Expected logs with this PR:

{"reqId":"3hxA7CSmglRj6RwCDqKJ","level":2,"time":"2023-02-28T09:42:33+00:00","remoteAddr":"10.0.2.27","user":"mountainUser1@mountain.tree.prv","app":"core","method":"GET","url":"\/remote.php\/dav\/files\/mountainUser1@mountain.tree.prv\/WindowsNetworkDrive\/foonly1\/kHlkYy0hYhvngkpQHcCnAkt5T28.gif?c=63fdcc8977b4c&x=32&y=32&forceIcon=0&preview=1","message":"Cannot get the underlying stream of class OCA\\windows_network_drive\\lib\\smbwrapper\\SMBStream with uri wnd:\/\/smb:\/\/WIN-EJBVQCVTVFU.mountain.tree.prv\/foobar\/foonly1\/kHlkYy0hYhvngkpQHcCnAkt5T28.gif. The OCA\\windows_network_drive\\lib\\smbwrapper\\SMBStream class should has a \"getSource\" method returning the underlying stream, or false \/ null if it isn't wrapping any other stream"}

As told in the log, the app will provide such method (still to be done)

[update-docs]

Thanks for opening this pull request! The maintainers of this repository would appreciate it if you would create a changelog item based on your changes.

[jvillafanez]

This is kind of a bug fix for #40600 , which hasn't been released yet. I don't think we need a changelog entry

[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
1 Code Smell

83.3% Coverage
0.0% Duplication