[clang] [clang][DependencyScanning] Implementing a Streaming Style API for By-name Scanning (PR #206800)

[Jan Svoboda via cfe-commits]

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jansvoboda11 wrote:

My understanding of this header was that it existed so that the separate scanning implementations (`CompilerInstanceWithContext` and `DependencyScanningWorker`) can share the same logic. With a single implementation of scanning, what prevents us from shuffling these helpers into implementation files?

https://github.com/llvm/llvm-project/pull/206800