
Reapply "[NFC][DebugInfo][DWARF] Create new low-level dwarf library (#… (#145959) This reapplies cbf781f0bdf2f680abbe784faedeefd6f84c246e, with fixes for the shared-library build and the unconventional sanitizer-runtime build. Original Description: This is the culmination of a series of changes described in [1]. Although somewhat large by line count, it is almost entirely mechanical, creating a new library in DebugInfo/DWARF/LowLevel. This new library has very minimal dependencies, allowing it to be used from more places than the normal DebugInfo/DWARF library--in particular from MC. 1. https://discourse.llvm.org/t/rfc-debuginfo-dwarf-refactor-into-to-lower-and-higher-level-libraries/86665/2