Fix memory leaks in RenderTextMac.

ui/gfx/render_text_mac.h

 // Copyright (c) 2012 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_RENDER_TEXT_MAC_H_
 #define UI_GFX_RENDER_TEXT_MAC_H_
 
 #include <ApplicationServices/ApplicationServices.h>
 
 #include <string>
@@ skipping 57 matching lines @@
 
   // Applies RenderText styles to |attr_string| with the given |ct_font|.
   void ApplyStyles(CFMutableAttributedStringRef attr_string, CTFontRef ct_font);
 
   // Updates |runs_| based on |line_| and sets |runs_valid_| to true.
   void ComputeRuns();
 
   // The Core Text line of text. Created by |EnsureLayout()|.
   base::mac::ScopedCFTypeRef<CTLineRef> line_;
 
+  // Array to hold CFAttributedString attributes that allows Core Text to hold
+  // weak references to them without leaking.
+  base::mac::ScopedCFTypeRef<CFMutableArrayRef> attributes_;
+
   // Visual dimensions of the text. Computed by |EnsureLayout()|.
   Size string_size_;
 
   // Common baseline for this line of text. Computed by |EnsureLayout()|.
   SkScalar common_baseline_;
 
   // Visual text runs. Only valid if |runs_valid_| is true. Computed by
   // |ComputeRuns()|.
   std::vector<TextRun> runs_;
 
   // Indicates that |runs_| are valid, set by |ComputeRuns()|.
   bool runs_valid_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderTextMac);
 };
 
 }  // namespace gfx
 
 #endif  // UI_GFX_RENDER_TEXT_MAC_H_