Revert 244086 "Reset only invalid custom margins."
Fixed the issue but introduced regressions.

> Reset only invalid custom margins.
> 
> BUG=332183
> 
> Review URL: https://codereview.chromium.org/131013005

TBR=vitalybuka@chromium.org

Review URL: https://codereview.chromium.org/140313002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@245020 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 245020