Removing -support naming convention

[jugglinmike]

When identifying tests, the WPT infrastructure ignores files whose name (not including extension) ends in -support. Today, only 13 files meet that criteria:

$ git ls-files | grep '\-support\.'

WebIDL/ecmascript-binding/constructors-support.html
css/css-values/vh-calc-support.html
css/css-values/vh-support.html
css/css-values/vh-zero-support.html
dom/traversal/traversal-support.js
event-timing/resources/event-timing-support.js
eventsource/eventsource-onmessage-realm-support.htm
fullscreen/rendering/fullscreen-pseudo-class-support.html
html/semantics/forms/resetting-a-form/reset-form-event-realm-support.html
html/syntax/parsing/DOMContentLoaded-defer-support.js
html/the-xhtml-syntax/parsing-xhtml-documents/xhtml-mathml-dtd-entity-support.htm
html/webappapis/scripting/events/resources/compiled-event-handler-settings-objects-support.html

The infrastructure also ignores files placed within subdirectories named "resources", "tools", or "support". That approach is far more common:

$ git ls-files | grep -E '(/|^)(resources|tools|support)/.*\.(html?|xht)' | wc -l
851

I'd like remove the infrastructure that recognizes the -support file name pattern and relocate the files that rely on it to an appropriately-named subdirectory. My motivation is to reduce the learning curve for contribution and limit the number of ways to express the same thing. In addition, four of the -support files listed above appear to actually be tests. If so, they are evidence that the naming scheme is prone to accidental opt-in.

Does anyone know of a reason why this simplification cannot or should not be made? @gsnedders or @jgraham, perhaps?

[gsnedders]

Yeah, this seems a bit surprising. Totally happy to drop this.

[foolip]

@gsnedders is this straightforward? Can I assign to you and plan to fix in the coming months?

[Ms2ger]

I guess this is fine, though I don't think we particularly need to start moving these tests. I expect the actual support files will end up in the default case in SourceFile.manifest_items() and be treated as support files anyway.