[clang] [clang][Driver] Add flag for setting SkipFunctionBodies (PR #100135)

[Ilya Biryukov via cfe-commits]

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@@ -0,0 +1,8 @@
+// Trivial check to ensure skip-function-bodies flag is propagated.
+//
+// RUN: %clang_cc1 -verify -skip-function-bodies -pedantic-errors %s
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ilya-biryukov wrote:

Could you also check in the test that this flag is not available outside of `-cc1`?

I think we really want to avoid that flag in the user-facing interface as it is expected to break a lot of things.

https://github.com/llvm/llvm-project/pull/100135