Merge to XFA: Switch from nonstd::unique_ptr to std::unique_ptr.

fpdfsdk/include/fsdk_actionhandler.h

Index: fpdfsdk/include/fsdk_actionhandler.h
diff --git a/fpdfsdk/include/fsdk_actionhandler.h b/fpdfsdk/include/fsdk_actionhandler.h
index 4417280a830b0857da67376e92392b0c418fdd9b..33f127d8c9a33596cf851b512c361878ea977582 100644
--- a/fpdfsdk/include/fsdk_actionhandler.h
+++ b/fpdfsdk/include/fsdk_actionhandler.h
@@ -7,10 +7,11 @@
 #ifndef FPDFSDK_INCLUDE_FSDK_ACTIONHANDLER_H_
 #define FPDFSDK_INCLUDE_FSDK_ACTIONHANDLER_H_
 
+#include <memory>
+
 #include "core/include/fpdfdoc/fpdf_doc.h"
 #include "core/include/fxcrt/fx_string.h"
 #include "fsdk_baseform.h"
-#include "third_party/base/nonstd_unique_ptr.h"
 
 class CFX_PtrList;
 class CPDFSDK_Annot;
@@ -116,7 +117,7 @@ class CPDFSDK_ActionHandler {
   void DoAction_SetOCGState(CPDFSDK_Document* pDocument,
                             const CPDF_Action& action);
 
-  nonstd::unique_ptr<CPDFSDK_FormActionHandler> m_pFormActionHandler;
+  std::unique_ptr<CPDFSDK_FormActionHandler> m_pFormActionHandler;
 };
 
 #endif  // FPDFSDK_INCLUDE_FSDK_ACTIONHANDLER_H_