[clang][Sema] Rename ActOnIVar parameter (llvm#66181)

I don't now squat about Objective C, but the extra variable (and cast)
seemed unnecessary and this is a good opportunity to re-format that ugly
parameter list.

Author: tbaederr

clang/include/clang/Sema/Sema.h

@@ -3499,9 +3499,8 @@ class Sema final {
 
   void ActOnLastBitfield(SourceLocation DeclStart,
                          SmallVectorImpl<Decl *> &AllIvarDecls);
-  Decl *ActOnIvar(Scope *S, SourceLocation DeclStart,
-                  Declarator &D, Expr *BitfieldWidth,
-                  tok::ObjCKeywordKind visibility);
+  Decl *ActOnIvar(Scope *S, SourceLocation DeclStart, Declarator &D,
+                  Expr *BitWidth, tok::ObjCKeywordKind visibility);
 
   // This is used for both record definitions and ObjC interface declarations.
   void ActOnFields(Scope *S, SourceLocation RecLoc, Decl *TagDecl,

clang/lib/Sema/SemaDecl.cpp

@@ -18556,13 +18556,10 @@ TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) {
 
 /// ActOnIvar - Each ivar field of an objective-c class is passed into this
 /// in order to create an IvarDecl object for it.
-Decl *Sema::ActOnIvar(Scope *S,
-                                SourceLocation DeclStart,
-                                Declarator &D, Expr *BitfieldWidth,
-                                tok::ObjCKeywordKind Visibility) {
+Decl *Sema::ActOnIvar(Scope *S, SourceLocation DeclStart, Declarator &D,
+                      Expr *BitWidth, tok::ObjCKeywordKind Visibility) {
 
   IdentifierInfo *II = D.getIdentifier();
-  Expr *BitWidth = (Expr*)BitfieldWidth;
   SourceLocation Loc = DeclStart;
   if (II) Loc = D.getIdentifierLoc();
 
@@ -18625,9 +18622,8 @@ Decl *Sema::ActOnIvar(Scope *S,
   }
 
   // Construct the decl.
-  ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, EnclosingContext,
-                                             DeclStart, Loc, II, T,
-                                             TInfo, ac, (Expr *)BitfieldWidth);
+  ObjCIvarDecl *NewID = ObjCIvarDecl::Create(
+      Context, EnclosingContext, DeclStart, Loc, II, T, TInfo, ac, BitWidth);
 
   if (II) {
     NamedDecl *PrevDecl = LookupSingleName(S, II, Loc, LookupMemberName,