Put CJBig2_SymbolDict's images in a CJBig2_List container.

core/src/fxcodec/jbig2/JBig2_List.h

 // 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
 
-#ifndef _JBIG2_LIST_H_
-#define _JBIG2_LIST_H_
+#ifndef CORE_SRC_FXCODEC_JBIG2_JBIG2_LIST_H_
+#define CORE_SRC_FXCODEC_JBIG2_JBIG2_LIST_H_
 
 #include <vector>
 
+// A poor man's ScopedVector for pointers of TYPE.
+// Owns all the pointers contained within and deletes them on destruction.
 template <class TYPE>
 class CJBig2_List {
  public:
   CJBig2_List() {}
 
   ~CJBig2_List() {
     clear();
   }
 
+  TYPE* get(size_t index) const { return m_vector[index]; }
+  TYPE* back() const { return m_vector.back(); }
+  size_t size() const { return m_vector.size(); }
+
+  // Deletes all the pointers contained within.
   void clear() {
     for (size_t i = 0; i < m_vector.size(); ++i)
       delete m_vector[i];
     m_vector.clear();
   }
 
+  // Takes ownership of |pItem|.
   void push_back(TYPE* pItem) { m_vector.push_back(pItem); }
 
-  size_t size() const { return m_vector.size(); }
-  void resize(size_t count) { m_vector.resize(count); }
-
-  TYPE* get(size_t index) { return m_vector[index]; }
-
-  TYPE* back() { return m_vector.back(); }
+  void resize(size_t count) {
+    for (size_t i = count; i < size(); ++i)
+      delete m_vector[i];
+    m_vector.resize(count);
+  }
 
  private:
   std::vector<TYPE*> m_vector;
 };
 
-#endif
+#endif  // CORE_SRC_FXCODEC_JBIG2_JBIG2_LIST_H_