Avoid base tree checkout using new base rpmdb

[fbruetting]

Host system details
F28SB

rpm-ostree:
 Version: 2018.5
 Git: ac21b217f86e9d22f11490a6c913139fefb360d8
 Features:
  - compose

Provide the output of rpm-ostree status.

State: idle; auto updates disabled
Deployments:
● ostree://fedora-workstation:fedora/28/x86_64/workstation
                   Version: 28.20180630.0 (2018-07-01 00:34:45)
                BaseCommit: a1d727723896673fcc9c9469a5030c084da639ee874093d3fb230c3e96a874c7
              GPGSignature: Valid signature by 128CF232A9371991C8A65695E08E7E629DB62FB1
           LayeredPackages: adapta-gtk-theme adobe-source-code-pro-fonts
                            adobe-source-sans-pro-fonts adobe-source-serif-pro-fonts
                            android-tools chrome-gnome-shell dconf-editor dnf easytag exa
                            exfat-utils ffmpeg-libs gcolor2 git glances gnome-tweaks
                            gnome-usage gpick htop iftop julia
                            linux-libertine-biolinum-fonts linux-libertine-fonts mosh neovim
                            powerline-go pv python3-matplotlib ripgrep setroubleshoot task
                            tilix tilix-nautilus tmux tokei youtube-dl zsh
             LocalPackages: rpmfusion-free-release-28-1.noarch
                            rpmfusion-nonfree-release-28-1.noarch

Expected vs actual behavior
Could you please check if the requested package(s) exist, before doing that checking out tree … stuff? If anything doesn’t exist or is already installed, the current implementation wastes quite some time.

[cgwalters]

Yeah, I find this annoying too. Here's an old PR I filed: #621

Since then, #1142 landed which is related. However, #1081 also "fixes" this by doing things in a quite different way.

[cgwalters]

PR in #1502

[cgwalters]

This was fixed by #1502