Split off CPDF_Document into its own .cpp/.h files.

fpdfsdk/src/fsdk_baseform.cpp

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "fpdfsdk/include/fsdk_baseform.h"
 
 #include <algorithm>
 #include <memory>
 
+#include "core/include/fpdfapi/cpdf_document.h"
 #include "fpdfsdk/include/formfiller/FFL_FormFiller.h"
 #include "fpdfsdk/include/fsdk_actionhandler.h"
 #include "fpdfsdk/include/fsdk_baseannot.h"
 #include "fpdfsdk/include/fsdk_define.h"
 #include "fpdfsdk/include/fsdk_mgr.h"
 #include "fpdfsdk/include/javascript/IJavaScript.h"
 #include "fpdfsdk/include/pdfwindow/PWL_Utils.h"
 
 #ifdef PDF_ENABLE_XFA
 #include "fpdfsdk/include/fpdfxfa/fpdfxfa_doc.h"
@@ skipping 2837 matching lines @@
       break;
     }
   }
 }
 
 CFX_FloatRect CBA_AnnotIterator::GetAnnotRect(const CPDFSDK_Annot* pAnnot) {
   CFX_FloatRect rcAnnot;
   pAnnot->GetPDFAnnot()->GetRect(rcAnnot);
   return rcAnnot;
 }