[clang][NFC] Refactor bit-fields in RawComment

Make them all of the same `unsigned` type, which brings `sizeof(RawComment)` down from 12 to 4 when compiling Clang for Microsoft ABI.

Author: Endilll

clang/include/clang/AST/RawCommentList.h

@@ -175,17 +175,22 @@ class RawComment {
   mutable StringRef RawText;
   mutable const char *BriefText = nullptr;
 
-  mutable bool RawTextValid : 1;   ///< True if RawText is valid
-  mutable bool BriefTextValid : 1; ///< True if BriefText is valid
+  LLVM_PREFERRED_TYPE(bool)
+  mutable unsigned RawTextValid : 1;
+  LLVM_PREFERRED_TYPE(bool)
+  mutable unsigned BriefTextValid : 1;
 
   LLVM_PREFERRED_TYPE(CommentKind)
   unsigned Kind : 3;
 
   /// True if comment is attached to a declaration in ASTContext.
-  bool IsAttached : 1;
+  LLVM_PREFERRED_TYPE(bool)
+  unsigned IsAttached : 1;
 
-  bool IsTrailingComment : 1;
-  bool IsAlmostTrailingComment : 1;
+  LLVM_PREFERRED_TYPE(bool)
+  unsigned IsTrailingComment : 1;
+  LLVM_PREFERRED_TYPE(bool)
+  unsigned IsAlmostTrailingComment : 1;
 
   /// Constructor for AST deserialization.
   RawComment(SourceRange SR, CommentKind K, bool IsTrailingComment,