Revert of cc: Early out sooner in UpdateTilePriorities when !CanHaveTilings().

Revert of cc: Early out sooner in UpdateTilePriorities when !CanHaveTilings(). (https://codereview.chromium.org/334953003/)

Reason for revert:
This appears to have broken: 
CreateTilingsEvenIfTwinHasNone
ManageTilingsWithNoRecording

http://build.chromium.org/p/chromium.mac/waterfall?builder=Mac%2010.7%20Tests%20(dbg)(1)

http://build.chromium.org/p/chromium.win/waterfall?builder=Win7%20Tests%20(dbg)(1)

http://build.chromium.org/p/chromium.linux/builders/Linux%20Tests%20%28dbg%29%282%29%2832%29/builds/13876

Original issue's description:
> cc: Early out sooner in UpdateTilePriorities when !CanHaveTilings().
> 
> Also, when we cleanup tilings on the active twin, we use the pending
> twin's ideal contents scale. But when the twin !CanHavTilings() there
> is no need to use that ideal scale and save tilings.
> 
> R=enne@chromium.org, enne
> 
> Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=278219

TBR=enne@chromium.org,danakj@chromium.org
NOTREECHECKS=true
NOTRY=true

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=278262

[jackhou1, 2014-06-19 03:59:31]

Created Revert of cc: Early out sooner in UpdateTilePriorities when
!CanHaveTilings().

[commit-bot: I haz the power, 2014-06-19 04:02:30]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/jackhou@chromium.org/348523005/1

[commit-bot: I haz the power, 2014-06-19 04:05:20]

Change committed as 278262