MIR inlining does not handle `SourceScopeLocalData`

[Aaron1011]

During the MIR inlining pass, we add scopes from the callee to Body.source_scopes in the caller. However, we do not update source_scope_local_data, which causes any inlined scopes to have no entry in the caller source_scope_local_data. This causes an ICE in Miri when we try to generate a stacktrace - however, the ICE occurs in rustc code, so it's possible that we might run across this without Miri.

[eddyb]

Sounds like a simple enough omission, but I'm surprised this doesn't break any of our mir-opt tests.

[Aaron1011]

I don't think this is E-Easy - source_scope_local_data is crate local, and it's not immediately obvious to me what the correct beehvaior is for cross-crate inlining.

[Dylan-DPC-zz]

@rustbot assign @Aaron1011