GitLab

- show 'More options' section only if there are more than 6 sections
  avaialble
- add ARIA labels for the color, copies, margins, layout and paper
  settings
- group Paper size section with other collapsible sections
- adjust Advanced options button size to fit the text

BUG=397741

Review URL: https://codereview.chromium.org/556363003

Cr-Commit-Position: refs/heads/master@{#294287}