After I installed the GNOME shell in Ubuntu, I decided that I didn't like having the "Close/Minimize/Maximize" buttons on the right, so I switched them over to the left using
gconftool-2 --set "/apps/metacity/general/button_layout" --type string "close, minimize, maximize:"
After resetting the shell, however, I found that with the GTK+ theme, only the close button shows up. Using system title bar and borders will make all the buttons appear, but I really want to use the theme because the system title bar makes the top bar too thick.
Logging out and back in didn't fix it, and I tried reinstalling Chrome, but the problem persists.