It does not make much sense to pipe (large) resource sets though the Wasm compilers.

Instead, resource files can be copied to the in-memory file system provided by emscripten, where they can be accessed using standard file API. The Qt resource system will then map qrc paths to filesystem paths, e.g. ":/foo" -> "/qt_resources/foo".

Build flow:

1. QRC copies resources to a qt_resources/ dir (on the host/build machine), instead of creating qrc_.o files
2. The emscripten file packing feature is used to populate the filesystem: "em++ --preload-file qt_resources/"