D18658: Modify search bar in the contextDrawer

[Carl Schwan]

ognarb added a dependency: D18716: Add a SearchField component.

REPOSITORY
  R223 Okular

REVISION DETAIL
  https://phabricator.kde.org/D18658

To: ognarb, #okular, ngraham
Cc: ngraham, okular-devel, tfella, darcyshen, aacid