Create SpaEnvironment

Make SettingsPageProviderRepository & SettingsEntryRepository defined as
Lazy, so it will not initialize when app start up.

Also move browseActivityClass & entryProviderAuthorities into the
SpaEnvironment.

Bug: 249028339
Test: Manual with Gallery App
Test: EntryRepo not shown in logcat when gallery start up
Test: EntryRepo only initialized once for debug activity
Change-Id: I1e2d5ff36a61e673b715e5f33c26dbbdcfb8b7cc