[clang] [-Wunsafe-buffer-usage] Check isValueDependent before EvaluateAsBooleanCondition (PR #172091)

[Ziqing Luo via cfe-commits]

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@@ -781,40 +817,6 @@ struct LibcFunNamePrefixSuffixParser {
   }
 };
 
-// Constant fold a conditional expression 'cond ? A : B' to
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ziqingluo-90 wrote:

Pulled the two functions out of the `libc_func_matchers ` namespace since they are more general.

https://github.com/llvm/llvm-project/pull/172091