[clang-tools-extra] [clangd][Mangler] Drop unknown compile options (PR #200001)

[via cfe-commits]

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@@ -525,6 +525,19 @@ TEST(CommandMangler, RespectsOriginalSysroot) {
                 Not(HasSubstr(testPath("fake/sysroot"))));
   }
 }
+TEST(CommandMangler, ClangUnknownArgs) {
+  // Check that clang-cl-specific will drop unknown flags
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Decodetalkers wrote:

Now I change the comment to clang++, I just copied the comment without check

https://github.com/llvm/llvm-project/pull/200001