Remove a few mutating ObjCCategoryDecl methods.

Remove
  -setClassInterface
  -setNextClassCategory
  -insertNextClassCategory

and combine them in the Create function.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@138817 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/ASTImporter.cpp b/lib/AST/ASTImporter.cpp
index b6e3e62..7174dbe 100644
--- a/lib/AST/ASTImporter.cpp
+++ b/lib/AST/ASTImporter.cpp
@@ -2986,15 +2986,12 @@
                                           Importer.Import(D->getAtLoc()),
                                           Loc, 
                                        Importer.Import(D->getCategoryNameLoc()), 
-                                          Name.getAsIdentifierInfo());
+                                          Name.getAsIdentifierInfo(),
+                                          ToInterface);
     ToCategory->setLexicalDeclContext(LexicalDC);
     LexicalDC->addDecl(ToCategory);
     Importer.Imported(D, ToCategory);
     
-    // Link this category into its class's category list.
-    ToCategory->setClassInterface(ToInterface);
-    ToCategory->insertNextClassCategory();
-    
     // Import protocols
     SmallVector<ObjCProtocolDecl *, 4> Protocols;
     SmallVector<SourceLocation, 4> ProtocolLocs;