linux: Both gtk and the aura port should set the icon theme name.

chrome/browser/ui/gtk/gtk_theme_service.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 CHROME_BROWSER_UI_GTK_GTK_THEME_SERVICE_H_
 #define CHROME_BROWSER_UI_GTK_GTK_THEME_SERVICE_H_
 
 #include <map>
 #include <vector>
 
@@ skipping 152 matching lines @@
 
   // Load theme data from preferences, possibly picking colors from GTK.
   virtual void LoadThemePrefs() OVERRIDE;
 
   // Let all the browser views know that themes have changed.
   virtual void NotifyThemeChanged() OVERRIDE;
 
   // Additionally frees the CairoCachedSurfaces.
   virtual void FreePlatformCaches() OVERRIDE;
 
+  // Gets the name of the current icon theme and passes it to our low level XDG
+  // integration.
+  void SetXDGIconTheme();
+
   // Extracts colors and tints from the GTK theme, both for the
   // ThemeService interface and the colors we send to webkit.
   void LoadGtkValues();
 
   // Reads in explicit theme frame colors from the ChromeGtkFrame style class
   // or generates them per our fallback algorithm.
   GdkColor BuildFrameColors(GtkStyle* frame_style);
 
   // Sets the values that we send to webkit to safe defaults.
   void LoadDefaultValues();
@@ skipping 122 matching lines @@
 
   // The default folder icon and default bookmark icon for the GTK theme.
   // These are static because the system can only have one theme at a time.
   // They are cached when they are requested the first time, and cleared when
   // the system theme changes.
   static base::LazyInstance<gfx::Image> default_folder_icon_;
   static base::LazyInstance<gfx::Image> default_bookmark_icon_;
 };
 
 #endif  // CHROME_BROWSER_UI_GTK_GTK_THEME_SERVICE_H_