Remove unused code for the metro window switcher button

Remove unused code for the metro window switcher button

We no longer use the "window switcher" button in Win8
metro mode, so remove all of the dead code related
to this. The button was used pre-Ash to allow easy
switching between a regular fullscreen browser window
and an incognito fullscreen window.

BUG=370913
TEST=none

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=268955

[tdanderson, 2014-05-07 14:57:32]

sky@ and erg@, can you please take a look?

[tdanderson, 2014-05-07 14:58:07]

Sorry, I meant cpu@, not erg@.

[sky, 2014-05-07 16:35:17]

Nice, LGTM

[tdanderson, 2014-05-07 17:06:32]

The CQ bit was checked by tdanderson@chromium.org

[commit-bot: I haz the power, 2014-05-07 17:10:25]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/tdanderson@chromium.org/272543003/1

[commit-bot: I haz the power, 2014-05-07 21:27:51]

Change committed as 268955