[clang] [llvm] Added partial support for compiling C++20 modules and header-units without scanning. (PR #147682)

[via llvm-commits]

github-actions[bot] wrote:

<!--PREMERGE ADVISOR COMMENT: Linux-->
# :penguin: Linux x64 Test Results

* 2016 tests passed
* 394 tests skipped
* 2436 tests failed

Failed tests and their output was too large to report. Download the build's log file to see the details.

If these failures are unrelated to your changes (for example tests are broken or flaky at HEAD), please open an issue at https://github.com/llvm/llvm-project/issues and add the `infrastructure` label.

https://github.com/llvm/llvm-project/pull/147682