[clang] [clang-tools-extra] [clang] Trim large(-ish) includes from common headers (PR #216946)

[Yanzuo Liu via cfe-commits]

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@@ -29,6 +29,7 @@
 #include "llvm/Option/ArgList.h"
 #include "llvm/Support/StringSaver.h"
 
+#include "llvm/Support/VirtualFileSystem.h"
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zwuis wrote:

```suggestion
#include "llvm/Support/VirtualFileSystem.h"

```


https://github.com/llvm/llvm-project/pull/216946