Usage of nsIProfileStartup Interface

 Copy user profile information to the current active profile.
 @param aItems   list of data items to migrate. see above for values.
 @param aStartup helper interface which is non-null if called during startup. 
 @param aProfile profile to migrate from, if there is more than one.

void migrate(in unsigned short aItems, in nsIProfileStartup aStartup, in wstring aProfile)

 Do profile migration.

 When this method is called, a default profile has been created;
 XPCOM has been initialized such that compreg.dat is in the
 profile; the directory service does *not* return a key for
 NS_APP_USER_PROFILE_50_DIR or any of the keys depending on an active
 profile. To figure out the directory of the "current" profile, use
 aStartup.directory.

 If your migrator needs to access services that use the profile (to
 set profile prefs or bookmarks, for example), use aStartup.doStartup.

 The startup code ignores COM exceptions thrown from this method.

void migrate(in nsIProfileStartup aStartup)