This directory includes various open-source third-party code that is used by Quickstep. Here's the description of the files:
download_and_patch_prerequisites.sh - Downloads the third party library source codes from their respective repositories and applies Quickstep specific patches.
reset_third_party_dir.sh - Removes the downloaded and patched third party and resets the third_party directory.
patches/ - Contains the patch files applied on the original third party source code files.
src/ - Contains the patched third party source code.
With the exception of the code in the tmb, iwyu, and the protobuf_cmake directories (which are part of the Quickstep project itself), all other libraries belong to their original authors and are governed by their respective licenses.