move IdentifierTable.h from liblex to libbasic.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@42730 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/AST/Decl.cpp b/AST/Decl.cpp
index da7aab9..e629e9c 100644
--- a/AST/Decl.cpp
+++ b/AST/Decl.cpp
@@ -13,7 +13,7 @@
 
 #include "clang/AST/Decl.h"
 #include "clang/AST/DeclObjC.h"
-#include "clang/Lex/IdentifierTable.h"
+#include "clang/Basic/IdentifierTable.h"
 using namespace clang;
 
 // temporary statistics gathering