Try 2: Completely redo how themes are stored on disk and processed at install time.

chrome/common/chrome_constants.h

 // Copyright (c) 2006-2008 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.
 
 // A handful of resource-like constants related to the Chrome application.
 
 #ifndef CHROME_COMMON_CHROME_CONSTANTS_H_
 #define CHROME_COMMON_CHROME_CONSTANTS_H_
 
 #include "base/file_path.h"
@@ skipping 22 matching lines @@
 extern const wchar_t kBrowserResourcesDll[];
 extern const FilePath::CharType kExtensionFileExtension[];
 
 // filenames
 extern const FilePath::CharType kArchivedHistoryFilename[];
 extern const FilePath::CharType kCacheDirname[];
 extern const FilePath::CharType kMediaCacheDirname[];
 extern const FilePath::CharType kOffTheRecordMediaCacheDirname[];
 extern const FilePath::CharType kAppCacheDirname[];
 extern const wchar_t kChromePluginDataDirname[];
-extern const FilePath::CharType kThemeImagesDirname[];
+extern const FilePath::CharType kThemePackFilename[];
 extern const FilePath::CharType kCookieFilename[];
 extern const FilePath::CharType kExtensionsCookieFilename[];
 extern const FilePath::CharType kHistoryFilename[];
 extern const FilePath::CharType kLocalStateFilename[];
 extern const FilePath::CharType kPreferencesFilename[];
 extern const FilePath::CharType kSafeBrowsingFilename[];
 extern const FilePath::CharType kSingletonSocketFilename[];
 extern const FilePath::CharType kSingletonLockFilename[];
 extern const FilePath::CharType kThumbnailsFilename[];
 extern const FilePath::CharType kNewTabThumbnailsFilename[];
@@ skipping 14 matching lines @@
 
 // The maximum number of characters of the document's title that we're willing
 // to send to the browser process.
 extern const size_t kMaxTitleChars;
 
 extern const bool kRecordModeEnabled;
 
 }  // namespace chrome
 
 #endif  // CHROME_COMMON_CHROME_CONSTANTS_H_