[clang] [clang-tools-extra] [clangd] Update clangDaemonTweaks to set symbol visibility macros (PR #112304)

[Saleem Abdulrasool via cfe-commits]

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@@ -114,7 +114,7 @@ macro(add_clang_library name)
     if(TARGET "obj.${name}")
       target_compile_definitions("obj.${name}" PUBLIC CLANG_BUILD_STATIC)
     endif()
-  elseif(NOT ARG_SHARED AND NOT ARG_STATIC)
+  elseif(NOT ARG_SHARED AND NOT ARG_STATIC AND NOT ARG_CLANG_IMPORT)
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compnerd wrote:

Then we should be using `if (NOT DEFINED ...)`. The syntax you have can check for the truthiness of the value.

https://github.com/llvm/llvm-project/pull/112304