Upstream dconf db settings for Ibus do not work correctly with Ubuntu

Ubuntu has changed how it handles input switching and no longer relies on the Ibus hotkey/trigger settings. The default upstream Ibus keybindings for input switching, however, are still installed unchanged in Ubuntu.

As a result, Control+Space, the default Ibus keybinding for input swithing, is needlessly set in the dconf db. This keybinding overrides Control+Space in other applications, notably Emacs and Eclipse auto-complete.

The default dconf db settings for Ibus are loaded by /etc/dconf/db/ibus/00-upstream-settings. The default settings in question are:

trigger=['Control+space', 'Zenkaku_Hankaku', 'Alt+Kanji', 'Alt+grave', 'Hangul', 'Alt+Release+Alt_R']
triggers=['<Control>space']

It's hard for most users to figure this out and the problem could be easily avoided by changing the default settings supplied from upstream.

This applies to 12.04, 13.10, 14.04.