Explicitly specify suitable font for combining-marks-position test

Explicitly specify suitable font for combining-marks-position test

The test case checks for correct rendering of combining marks above the text,
instead of for example extending the run length by rendering them as a separate
glyph. For the purpose of a robust test case, a font should be chosen that has
all the required glyphs. Times New Roman on Linux - which is default selected
otherwise - does have a glyph for Heh but does not have a glyph for the Hamza
combining mark.

Before grapheme cluster font selection, Heh is rendered from Times New Roman,
with a Hamza glyph from DejaVu Sans above - which is not optimal. After grapheme
cluster based font selection, Heh and Hamza are combined from DejaVu Sans,
however, rendered as an isolated glyph separate from the rest of the run, which
is not optimal either.

More discussion on what is the real fix, e.g. selecting DejaVu Sans for the
whole run is in the bug.

BUG=535141
R=behdad,eae

Committed: https://crrev.com/57f03b0def938c5af026fc7226e5bdae25b78f7d
Cr-Commit-Position: refs/heads/master@{#350513}

[drott, 2015-09-23 12:10:27]

The CQ bit was checked by drott@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2015-09-23 12:10:45]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1363893002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1363893002/1

[commit-bot: I haz the power, 2015-09-23 12:16:20]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-09-23 12:16:20]

Dry run: Try jobs failed on following builders:
  mac_chromium_rel_ng on tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_rel_...)

[eae, 2015-09-23 13:51:37]

LGTM

[drott, 2015-09-23 15:44:53]

rebased to chromium repo

[drott, 2015-09-24 08:48:19]

The CQ bit was checked by drott@chromium.org

[drott, 2015-09-24 08:48:19]

The patchset sent to the CQ was uploaded after l-g-t-m from eae@chromium.org
Link to the patchset: https://codereview.chromium.org/1363893002/#ps20001
(title: "rebased to chromium repo")

[commit-bot: I haz the power, 2015-09-24 08:48:38]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1363893002/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1363893002/20001

[commit-bot: I haz the power, 2015-09-24 09:25:22]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-09-24 09:26:38]

Patchset 2 (id:??) landed as
https://crrev.com/57f03b0def938c5af026fc7226e5bdae25b78f7d
Cr-Commit-Position: refs/heads/master@{#350513}