Start proxying CPDFSDK_Document methods through CPDFSDK_FormFillEnvironment

fpdfsdk/cpdfsdk_interform.h

Index: fpdfsdk/cpdfsdk_interform.h
diff --git a/fpdfsdk/cpdfsdk_interform.h b/fpdfsdk/cpdfsdk_interform.h
index 617a1066d7720b1b94a56d72875332df3e7140f1..a2c4c0685c6acd5b0ed8a0f9fc5ded99939fac87 100644
--- a/fpdfsdk/cpdfsdk_interform.h
+++ b/fpdfsdk/cpdfsdk_interform.h
@@ -14,13 +14,14 @@
 #include "core/fpdfdoc/ipdf_formnotify.h"
 #include "core/fxcrt/fx_basic.h"
 #include "core/fxge/fx_dib.h"
+#include "fpdfsdk/cpdfsdk_document.h"
 
 class CPDF_Dictionary;
 class CPDF_FormControl;
 class CPDF_FormField;
 class CPDF_InterForm;
 class CPDF_Object;
-class CPDFSDK_Document;
+class CPDFSDK_FormFillEnvironment;
 class CPDFSDK_Widget;
 
 #ifdef PDF_ENABLE_XFA
@@ -34,7 +35,9 @@ class CPDFSDK_InterForm : public IPDF_FormNotify {
   ~CPDFSDK_InterForm() override;
 
   CPDF_InterForm* GetInterForm() const { return m_pInterForm.get(); }
-  CPDFSDK_Document* GetDocument() const { return m_pDocument; }
+  CPDFSDK_FormFillEnvironment* GetFormFillEnv() const {
+    return m_pDocument->GetEnv();
+  }
 
   FX_BOOL HighlightWidgets();