GTTF: Enable glibcxx debug mode for Debug builds by default.

ui/gfx/image/image_family.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_GFX_IMAGE_IMAGE_FAMILY_H_
 #define UI_GFX_IMAGE_IMAGE_FAMILY_H_
 
 #include <iterator>
 #include <map>
 #include <utility>
@@ skipping 30 matching lines @@
  public:
   // Type for iterating over all images in the family, in order.
   // Dereferencing this iterator returns a gfx::Image.
   class GFX_EXPORT const_iterator :
     std::iterator<std::bidirectional_iterator_tag, const gfx::Image> {
    public:
     const_iterator();
 
     const_iterator(const const_iterator& other);
 
+    ~const_iterator();
+
     const_iterator& operator++() {
       ++map_iterator_;
       return *this;
     }
 
     const_iterator operator++(int /*unused*/) {
       const_iterator result(*this);
       ++(*this);
       return result;
     }
@@ skipping 86 matching lines @@
   // |map_| of aspect ratio |aspect|.
   const gfx::Image* GetWithExactAspect(float aspect, int width) const;
 
   // Map from (aspect ratio, width) to image.
   std::map<MapKey, gfx::Image> map_;
 };
 
 }  // namespace gfx
 
 #endif  // UI_GFX_IMAGE_IMAGE_FAMILY_H_