Move fs-checkpoint checking logic into InstallUtilsHost Bug: 160296318 Test: atest StagedInstallTest Test: atest RollbackManagerHostTest Change-Id: Ie8be624c03f2d9b7c7a4fbeda58d0493de8bac0d Merged-In: Ie8be624c03f2d9b7c7a4fbeda58d0493de8bac0d (cherry picked from commit 13866a821de6427a8842d82786b71b4bcd75eea7)