[clang] [clang] Rework `hasBooleanRepresentation`. (PR #136038)

[John McCall via cfe-commits]

================
@@ -5238,6 +5238,14 @@ inline bool IsEnumDeclScoped(EnumDecl *ED) {
   return ED->isScoped();
 }
 
+/// Return the integer type corresponding to the given decl.
+///
+/// We use this function to break a cycle between the inline definitions in
+/// Type.h and Decl.h.
+inline QualType GetEnumDeclIntegerType(EnumDecl *ED) {
----------------
rjmccall wrote:

We've generally been naming new functions with lower-case letters.

https://github.com/llvm/llvm-project/pull/136038