Adds commit '79b6681aadcb53c27d1052e5f8a0e82a981dbf2f' from https://github.com/KhronosGroup/SPIRV-Headers as 'third_party/SPIRV-Headers' Commands: git subtree add --prefix third_party/SPIRV-Headers https://github.com/KhronosGroup/SPIRV-Headers 79b6681aadcb53c27d1052e5f8a0e82a981dbf2f --squash Bug: b/123642959 Change-Id: I39d6f1aff817ec9ed527c01eb631c99d81a17a95
