Revert of Fix slow repaint object registration

Revert of Fix slow repaint object registration (patchset #1 id:1 of https://codereview.chromium.org/1234153003/)

Reason for revert:
Speculative revert: appears to have broken Linux MSAN bots. Author suggested there was in uninited varible use in their code.

Original issue's description:
> Reland of Fix slow repaint object registration (patchset #1 id:1 of https://codereview.chromium.org/1224083019/)
> 
> Reason for revert:
> This patch was not the cause, relanding.
> 
> Original issue's description:
> > Revert of Fix slow repaint object registration (patchset #2 id:20001 of https://codereview.chromium.org/1240443003/)
> > 
> > Reason for revert:
> > Speculative revert: appears to have broken Linux MSAN bots.
> > 
> > http://build.chromium.org/p/chromium.webkit/builders/WebKit%20Linux%20MSAN/builds/4413
> > 
> > 
> > Original issue's description:
> > > Fix slow repaint object registration
> > > 
> > > The LayoutView now paints background, so the special condition to accelerate
> > > frame scrolling with fixed root background should be updated as well.
> > > 
> > > As a drive-by fix, this CL also corrects slow repaint object accounting so
> > > we no longer leak slow repaint object count.
> > > 
> > > BUG=506002
> > > 
> > > Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=198894
> > 
> > TBR=vollick@chromium.org,trchen@chromium.org
> > NOPRESUBMIT=true
> > NOTREECHECKS=true
> > NOTRY=true
> > BUG=506002
> > 
> > Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=198913
> 
> TBR=vollick@chromium.org,trchen@chromium.org,rtoy@chromium.org,yosin@chromium.org
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
> BUG=506002
> 
> Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=198920

TBR=vollick@chromium.org,trchen@chromium.org,rtoy@chromium.org,yosin@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=506002
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=198942

[Noel Gordon, 2015-07-15 08:35:44]

Created Revert of Fix slow repaint object registration

[commit-bot: I haz the power, 2015-07-15 08:35:52]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1234183003/1

[commit-bot: I haz the power, 2015-07-15 08:36:28]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=198942

[Noel Gordon, 2015-07-15 08:37:58]

"Author suggested there was in uninited varible use in their code" [1]

[1] https://codereview.chromium.org/1234153003/#msg4

[Noel Gordon, 2015-07-15 10:20:19]

On 2015/07/15 08:37:58, noel gordon wrote:
> "Author suggested there was in uninited varible use in their code" [1]
> 
> [1] https://codereview.chromium.org/1234153003/#msg4

And the
http://build.chromium.org/p/chromium.webkit/builders/WebKit%20Linux%20MSAN/bu...
went green after this revert.

[Noel Gordon, 2015-07-15 12:12:46]

Also the next 3 MSAN build, and unblocked the blink roll
https://codereview.chromium.org/1234183003 allowing it ot proceeed.

[Noel Gordon, 2015-07-15 12:12:52]

Also the next 3 MSAN build, and unblocked the blink roll
https://codereview.chromium.org/1234183003 allowing it to proceeed.