One test case I wrote recently was to import a lowered function into a
wasm module and then immediately export it. This previously didn't work
because trampoline lookup would fail as the original
`VMCallerCheckedAnyfunc` function pointer points into the
`trampoline_obj` of a component which wasn't registered with the
`ModuleRegistry`. This plumbs through the necessary configuration to get
that all hooked up.
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