Again reverting an attempt to convert the DeclSpec enums into scoped enums.
  - reverts r321622, r321625, and r321626.
  - the use of bit-fields is still resulting in warnings - even though we can use static-asserts to harden the code and ensure the bit-fields are wide enough.  The bots still complain of warnings being seen.
  - to silence the warnings requires specifying the bit-fields with the underlying enum type (as opposed to the enum type itself), which then requires lots of unnecessary static casts of each enumerator within DeclSpec to the underlying-type, which even though could be seen as implementation details, it does hamper readability - and given the additional litterings, makes me question the value of the change.

So in short - I give up (for now at least).  

Sorry about the noise.

llvm-svn: 321628
diff --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
index 9cc1967..7c6af57 100644
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -1152,7 +1152,7 @@
 }
 
 DeclResult
-Sema::CheckClassTemplate(Scope *S, TypeSpecifierType TagSpec, TagUseKind TUK,
+Sema::CheckClassTemplate(Scope *S, unsigned TagSpec, TagUseKind TUK,
                          SourceLocation KWLoc, CXXScopeSpec &SS,
                          IdentifierInfo *Name, SourceLocation NameLoc,
                          AttributeList *Attr,
@@ -7336,7 +7336,7 @@
 }
 
 DeclResult
-Sema::ActOnClassTemplateSpecialization(Scope *S, TypeSpecifierType TagSpec,
+Sema::ActOnClassTemplateSpecialization(Scope *S, unsigned TagSpec,
                                        TagUseKind TUK,
                                        SourceLocation KWLoc,
                                        SourceLocation ModulePrivateLoc,
@@ -8506,7 +8506,7 @@
 Sema::ActOnExplicitInstantiation(Scope *S,
                                  SourceLocation ExternLoc,
                                  SourceLocation TemplateLoc,
-                                 TypeSpecifierType TagSpec,
+                                 unsigned TagSpec,
                                  SourceLocation KWLoc,
                                  const CXXScopeSpec &SS,
                                  TemplateTy TemplateD,
@@ -8794,7 +8794,7 @@
 Sema::ActOnExplicitInstantiation(Scope *S,
                                  SourceLocation ExternLoc,
                                  SourceLocation TemplateLoc,
-                                 TypeSpecifierType TagSpec,
+                                 unsigned TagSpec,
                                  SourceLocation KWLoc,
                                  CXXScopeSpec &SS,
                                  IdentifierInfo *Name,
@@ -9310,7 +9310,7 @@
 }
 
 TypeResult
-Sema::ActOnDependentTag(Scope *S, TypeSpecifierType TagSpec, TagUseKind TUK,
+Sema::ActOnDependentTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
                         const CXXScopeSpec &SS, IdentifierInfo *Name,
                         SourceLocation TagLoc, SourceLocation NameLoc) {
   // This has to hold, because SS is expected to be defined.