Add a generic account chooser/add account flow for apps.
The activity is launched as follows:
Account account1 = new Account("account1@gmail.com", "com.google")
Account account2 = new Account("account2@gmail.com", "com.google")
ArrayList<Account> accounts = new ArrayList<Account>();
accounts.add(account1);
accounts.add(account2);
String[] accountTypes = new String[]{"com.google", "com.android.exchange"};
Bundle addAccountOptions = null;
Intent intent = AccountManager.newChooseAccountIntent(account1, accounts,
accountTypes, addAccountOptions);
startActivityForResult(intent, 0);
Change-Id: I05a467bdc3552a2e39397b0182879351f4324389
89e063113c