[6.0] Improve performance of precompiled module invalidation in incremental builds #1627
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Explanation: Simplify the explicit precompiled module invalidation algorithm for incremental builds so that it only visits each module in the graph once, avoiding a slowdown in the worst case where all/most modules in the graph are invalidated
Risk: Low. The changes are narrow in scope and covered by existing tests in the incremental build suite.
Testing: Existing incremental build correctness tests
Original PR: #1626
Reviewer: @artemcm