llvm-project

77800224 - Reapply "[PDB][llvm-pdbutil] Add DXContainer support for `pdb2yaml` and `yaml2pdb`" (#200413)

Reapply "[PDB][llvm-pdbutil] Add DXContainer support for `pdb2yaml` and `yaml2pdb`" (#200413) This reapplies #198351 with a fix for `-Wchanges-meaning` causing an error in `PdbYaml.h`. Original description: This patch enables the following: 1. Attempting to parse a `DXContainer` from stream 5 (generated by DirectX tools) of a PDB file, to be used later in `llvm-pdbutil`. 2. Outputting a PDB file with a built in DXContainer as YAML. Existing DirectX tools form a PDB container with empty DBI, TPI and IPI streams, so this patch also allows them to be empty when dumping a PDB file as YAML. 3. Creating a PDB file from YAML with an built in DXContainer. When creating a PDB with a DXContainer, streams DBI, TPI and IPI can be completely empty, so this patch also includes adjustments to allow forming such a PDB file. This is done to maintain compatibility with other DirectX tools.