Make CPDF_TextState have a CPDF_TextStateData rather than inheriting one.

core/fpdfapi/fpdf_page/cpdf_allstates.cpp

 // Copyright 2016 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 "core/fpdfapi/fpdf_page/cpdf_allstates.h"
 
 #include "core/fpdfapi/fpdf_page/pageint.h"
 #include "core/fpdfapi/fpdf_parser/include/cpdf_array.h"
@@ skipping 80 matching lines @@
         break;
       }
       case FXBSTR_ID('R', 'I', 0, 0):
         m_GeneralState.SetRenderIntent(pObject->GetString());
         break;
       case FXBSTR_ID('F', 'o', 'n', 't'): {
         CPDF_Array* pFont = pObject->AsArray();
         if (!pFont)
           break;
 
-        m_TextState.GetPrivateCopy()->m_FontSize = pFont->GetNumberAt(1);
+        m_TextState.SetFontSize(pFont->GetNumberAt(1));
         m_TextState.SetFont(pParser->FindFont(pFont->GetStringAt(0)));
         break;
       }
       case FXBSTR_ID('T', 'R', 0, 0):
         if (pGS->KeyExist("TR2")) {
           continue;
         }
       case FXBSTR_ID('T', 'R', '2', 0):
         pGeneralState->m_pTR =
             (pObject && !pObject->IsName()) ? pObject : nullptr;
@@ skipping 65 matching lines @@
       case FXBSTR_ID('A', 'I', 'S', 0):
         pGeneralState->m_AlphaSource = pObject->GetInteger();
         break;
       case FXBSTR_ID('T', 'K', 0, 0):
         pGeneralState->m_TextKnockout = pObject->GetInteger();
         break;
     }
   }
   pGeneralState->m_Matrix = m_CTM;
 }