SharedPreferences Placeholder instead of SharedPreferences

[felixgabler]

With the Null Safety, you introduced a placeholder object for SharedPreferences:

flutter_pref/pref/lib/src/service/shared_preferences.dart

Line 12 in 45ad35d

class SharedPreferences {

[DavBfr]

Yes, you're right! That was because SharedPreferences was not yet null-safe. I'll fix that.

[DavBfr]

Published version 2.0.0.