Move dialogs to the left, make arrows point right

Change-Id: If8fc4ca5f902b3dc3271a33c44554d4e46faadb8
Style fixes for the UI changes

I decided to fix them all at once since we're merging all of these
patches together anyway. I can pull changes into other patches if
absolutely necessary.

Also fixes the dialog open/close handlers for the canvas click event,
and leaves the reuse dialog open on next/prev.

Change-Id: Id1564425442aec72e5e41f2f80986d8a104dd92c
Move focus event handlers to mmv.ui.Element

Needed to make sure the download dialog can use the handlers.

Change-Id: If62146f1181f0e722be691f61e5fdc133c9b3795
Fix bug where download dialog doesn't unattach

Change-Id: I02c45bf9d0aea8e92d02cb80f266f6c83633a50c
Merge "Move dialogs to the left, make arrows point right"
Merge "Style fixes for the UI changes"
Merge "Move focus event handlers to mmv.ui.Element"
Merge "Fix bug where download dialog doesn't unattach"