Stub out and start using a Decl::Destroy() method.

llvm-svn: 49532
diff --git a/clang/lib/AST/Decl.cpp b/clang/lib/AST/Decl.cpp
index 2ef31e4..43da07c 100644
--- a/clang/lib/AST/Decl.cpp
+++ b/clang/lib/AST/Decl.cpp
@@ -329,6 +329,10 @@
   return (*DeclAttrs)[this];
 }
 
+void Decl::Destroy(ASTContext& C) const {
+  C.getAllocator().Deallocate((void *)this);
+}
+
 //===----------------------------------------------------------------------===//
 // DeclContext Implementation
 //===----------------------------------------------------------------------===//