Move theme files in chrome/browser/ into a themes/ subdir.

chrome/browser/themes/browser_theme_pack.h

Index: chrome/browser/themes/browser_theme_pack.h
diff --git a/chrome/browser/browser_theme_pack.h b/chrome/browser/themes/browser_theme_pack.h
similarity index 98%
rename from chrome/browser/browser_theme_pack.h
rename to chrome/browser/themes/browser_theme_pack.h
index c5b20ebcb6c3e73e9b54d8e8158b5ef0ef4cba35..85d27af073be314209471bf6c9e8e06c20c0c230 100644
--- a/chrome/browser/browser_theme_pack.h
+++ b/chrome/browser/themes/browser_theme_pack.h
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef CHROME_BROWSER_BROWSER_THEME_PACK_H_
-#define CHROME_BROWSER_BROWSER_THEME_PACK_H_
+#ifndef CHROME_BROWSER_THEMES_BROWSER_THEME_PACK_H_
+#define CHROME_BROWSER_THEMES_BROWSER_THEME_PACK_H_
 #pragma once
 
 #include <map>
@@ -223,4 +223,4 @@ class BrowserThemePack : public base::RefCountedThreadSafe<BrowserThemePack> {
   DISALLOW_COPY_AND_ASSIGN(BrowserThemePack);
 };
 
-#endif  // CHROME_BROWSER_BROWSER_THEME_PACK_H_
+#endif  // CHROME_BROWSER_THEMES_BROWSER_THEME_PACK_H_