Avoid endless loop deleting CFGAS_GEFont.

xfa/fxfa/app/xfa_textpiece.cpp

 // Copyright 2017 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 "xfa/fxfa/app/xfa_textpiece.h"
 
 #include "xfa/fxfa/app/cxfa_linkuserdata.h"
 
 XFA_TextPiece::XFA_TextPiece()
-    : pszText(nullptr), pFont(nullptr), pLinkData(nullptr) {}
+    : pszText(nullptr), pWidths(nullptr), pFont(nullptr), pLinkData(nullptr) {}
 
 XFA_TextPiece::~XFA_TextPiece() {
   if (pLinkData)
     pLinkData->Release();
+
+  FX_Free(pszText);
+  FX_Free(pWidths);
 }