Have /storage always point to sdcardfs by default.

This is a partial revert of change
Idf851b3a42910e0ce8fdd75daea1cce91dd1aa98, and brings us back to the
state we shipped in Q.

The default behavior for now is that we want native daemons to use the
default sdcardfs view, as they did before. Zygote-spawned apps will then
get the correct view assigned to them as they get spawned.

Bug: 146189163
Test: atest AdoptableHostTest
Change-Id: I2248f39e029138962a41a6ead944431414c901ad