Revert "Reland "[DebugMetadata][DwarfDebug] Support function-local types in...

Revert "Reland "[DebugMetadata][DwarfDebug] Support function-local types in lexical block scopes (4/7)" (2)"

This reverts commit cb9ac705.
It causes an assert in clang:
virtual void llvm::DwarfDebug::endFunctionImpl(const llvm::MachineFunction*): Assertion `LScopes.getAbstractScopesList().size() == NumAbstractSubprograms && "getOrCreateAbstractScope() inserted an abstract subprogram scope"' failed.
https://bugs.chromium.org/p/chromium/issues/detail?id=1456288#c2