Drop the ASTContext.h include from DeclFriend.h and DeclTemplate.h.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@159723 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/AnalysisDeclContext.cpp b/lib/Analysis/AnalysisDeclContext.cpp
index b618569..32b1fcf 100644
--- a/lib/Analysis/AnalysisDeclContext.cpp
+++ b/lib/Analysis/AnalysisDeclContext.cpp
@@ -12,6 +12,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "clang/AST/ASTContext.h"
 #include "clang/AST/Decl.h"
 #include "clang/AST/DeclObjC.h"
 #include "clang/AST/DeclTemplate.h"