Revert r276069: MSVC bots not happy

llvm-svn: 276074
diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index 05b30a4..e54c88f 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -651,10 +651,6 @@
                                            cast<TemplateTemplateParmDecl>(*P)));
   }
 
-  assert(!TTP->getRequiresClause() &&
-         "Unexpected requires-clause on template template-parameter");
-  LLVM_CONSTEXPR Expr *const CanonRequiresClause = nullptr;
-
   TemplateTemplateParmDecl *CanonTTP
     = TemplateTemplateParmDecl::Create(*this, getTranslationUnitDecl(), 
                                        SourceLocation(), TTP->getDepth(),
@@ -664,8 +660,7 @@
                          TemplateParameterList::Create(*this, SourceLocation(),
                                                        SourceLocation(),
                                                        CanonParams,
-                                                       SourceLocation(),
-                                                       CanonRequiresClause));
+                                                       SourceLocation()));
 
   // Get the new insert position for the node we care about.
   Canonical = CanonTemplateTemplateParms.FindNodeOrInsertPos(ID, InsertPos);