Move a method from IdentifierTable.h out of line and remove the SmallString include.

Fix all the transitive include users.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@149783 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/StaticAnalyzer/Checkers/BasicObjCFoundationChecks.cpp b/lib/StaticAnalyzer/Checkers/BasicObjCFoundationChecks.cpp
index cbe144b..bb1c613 100644
--- a/lib/StaticAnalyzer/Checkers/BasicObjCFoundationChecks.cpp
+++ b/lib/StaticAnalyzer/Checkers/BasicObjCFoundationChecks.cpp
@@ -28,6 +28,7 @@
 #include "clang/AST/Expr.h"
 #include "clang/AST/ExprObjC.h"
 #include "clang/AST/ASTContext.h"
+#include "llvm/ADT/SmallString.h"
 
 using namespace clang;
 using namespace ento;