[AST] Use scoped enum for attribute kinds

Align with other kind enum e.g. DeclKind.

Author: rintaro

include/swift/APIDigester/ModuleAnalyzerNodes.h

@@ -394,7 +394,7 @@ class SDKNodeDecl: public SDKNode {
   bool isImplicit() const { return IsImplicit; };
   bool isStatic() const { return IsStatic; };
   bool isOverriding() const { return IsOverriding; };
-  bool isOptional() const { return hasDeclAttribute(DeclAttrKind::DAK_Optional); }
+  bool isOptional() const { return hasDeclAttribute(DeclAttrKind::Optional); }
   bool isOpen() const { return IsOpen; }
   bool isInternal() const { return IsInternal; }
   bool isABIPlaceholder() const { return IsABIPlaceholder; }
@@ -492,9 +492,7 @@ class SDKNodeTypeNominal : public SDKNodeType {
 class SDKNodeTypeFunc : public SDKNodeType {
 public:
   SDKNodeTypeFunc(SDKNodeInitInfo Info);
-  bool isEscaping() const {
-    return hasTypeAttribute(TypeAttrKind::TAK_NoEscape);
-  }
+  bool isEscaping() const { return hasTypeAttribute(TypeAttrKind::NoEscape); }
   static bool classof(const SDKNode *N);
   void diagnose(SDKNode *Right) override;
 };

include/swift/AST/ASTBridgingWrappers.def

@@ -61,7 +61,7 @@
 #include "swift/AST/PatternNodes.def"
 
 #ifndef DECL_ATTR
-#define SIMPLE_DECL_ATTR(X, CLASS, OPTIONS, CODE)
+#define SIMPLE_DECL_ATTR(...)
 #define DECL_ATTR(_, Id, ...) AST_BRIDGING_WRAPPER_NONNULL(Id##Attr)
 #endif
 #include "swift/AST/Attr.def"

include/swift/AST/ASTVisitor.h

@@ -137,14 +137,13 @@ class ASTVisitor {
 
   AttributeRetTy visit(DeclAttribute *A, Args... AA) {
     switch (A->getKind()) {
-#define DECL_ATTR(_, CLASS, ...)                           \
-    case DAK_##CLASS:                                              \
-      return static_cast<ImplClass*>(this)                        \
-               ->visit##CLASS##Attr(static_cast<CLASS##Attr*>(A), \
-                                    ::std::forward<Args>(AA)...);
+#define DECL_ATTR(_, CLASS, ...)                                               \
+  case DeclAttrKind::CLASS:                                                    \
+    return static_cast<ImplClass *>(this)->visit##CLASS##Attr(                 \
+        static_cast<CLASS##Attr *>(A), ::std::forward<Args>(AA)...);
 #include "swift/AST/Attr.def"
 
-    case DAK_Count:
+    case DeclAttrKind::Count:
       llvm_unreachable("Not an attribute kind");
     }
   }