Fix height of the viewer-pane in Material Design PDF Viewer

Fix height of the viewer-pane in Material Design PDF Viewer

After making the toolbar in the Material Design PDF Viewer thinner (Issue 891563004) a prominent gap was left between it and the viewer pane.
Now the viewer-pane has been adjusted to fill this gap.

BUG=110020
Committed: https://crrev.com/c790eac53913c4c48018cc5313c10a940f2ccd12
Cr-Commit-Position: refs/heads/master@{#314496}

[Alexandre Carlton, 2015-02-03 22:30:21]

alexandrec@chromium.org changed reviewers:
+ raymes@chromium.org, sammc@chromium.org

[Sam McNally, 2015-02-03 22:49:47]

lgtm

[raymes, 2015-02-04 00:54:54]

lgtm

[Alexandre Carlton, 2015-02-04 02:40:17]

The CQ bit was checked by alexandrec@chromium.org

[commit-bot: I haz the power, 2015-02-04 02:40:32]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/895193002/1

[commit-bot: I haz the power, 2015-02-04 03:58:53]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-02-04 03:59:58]

Patchset 1 (id:??) landed as
https://crrev.com/c790eac53913c4c48018cc5313c10a940f2ccd12
Cr-Commit-Position: refs/heads/master@{#314496}