This check in brings in the following updates in theme-related code: -...

This check in brings in the following updates in theme-related code: - getInstalledThemes name is changed to getInstalledThemePackages; - the new method returns a list of PackageInfo objects (instead of ThemeInfo); - "themeapk" tag was renamed to "theme"; - since it is allowed to specify multiple themes in a single theme package (the manifest file may contain more than one theme tag), PackageInfo object contains an array of ThemeInfo elements.

This check in implements features which are used by the ShowTheme app (checked in yesterday).