Revert of NTP Zombie Code Slayer Part IV: Most Visited

Revert of NTP Zombie Code Slayer Part IV: Most Visited (patchset #6 id:100001 of https://codereview.chromium.org/1129903008/)

Reason for revert:
Duplicate pref registration on Android somehow.

Original issue's description:
> NTP Zombie Code Slayer Part IV: Most Visited
>
> This is where things get complicated.
>
> NTP4 had a most visited pane.  It showed your top sites.
> So does the current NTP; so I'm trying to remove everything
> that deals with most visited tiles on NTP4 without accidentally
> breaking the same named thing on the current NTP.
>
> Here's what used to exist that I'm trying to remove:
> http://bostandjiev.com/Content/Google/chrome.jpg
>
> Here's what currently exists that I'm trying not to break:
> http://cdn.ghacks.net/wp-content/uploads/2013/04/chrome-new-tab-page.jpg
>
> BUG=329637
>
> Committed: https://crrev.com/1fc345cd960f7efd4e6b07d1f050615239d82d60
> Cr-Commit-Position: refs/heads/master@{#330845}

TBR=samarth@chromium.org,rdevlin.cronin@chromium.org,sky@chromium.org,xiyuan@chromium.org,gab@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=329637
Committed: https://crrev.com/b0909984cb70d10aebe20754703df38efa237525
Cr-Commit-Position: refs/heads/master@{#330876}

[Dan Beam, 2015-05-21 02:34:29]

Created Revert of NTP Zombie Code Slayer Part IV: Most Visited

[commit-bot: I haz the power, 2015-05-21 02:35:39]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1151563005/1

[Yaron, 2015-05-21 02:36:04]

On 2015/05/21 at 02:35:39, commit-bot wrote:
> CQ is trying da patch. Follow status at
>  https://chromium-cq-status.appspot.com/patch-status/1151563005/1

lgtm

[newt (away), 2015-05-21 02:36:10]

newt@chromium.org changed reviewers:
+ newt@chromium.org

[newt (away), 2015-05-21 02:36:11]

lgtm

[commit-bot: I haz the power, 2015-05-21 02:37:36]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-05-21 02:38:31]

Patchset 1 (id:??) landed as
https://crrev.com/b0909984cb70d10aebe20754703df38efa237525
Cr-Commit-Position: refs/heads/master@{#330876}