For multiline text use the maximum of the string height and the line height while calculating the h…

For multiline text use the maximum of the string height and the line height while calculating the height of the text being displayed.

The current code in the Canvas::SizeStringFloat function uses the passed in line_height while calculating the total
height for multiline text. This works for all cases except for DirectWrite where in the text height is a touch bigger
leading to it getting clipped. Example where this breaks is in the message center notifications where the line height
is hardcoded to 18. We could fix notification views. However it seems like fixing canvas_skia would be better.

BUG=429108
Committed: https://crrev.com/a0b11455d6dcf2fd59df7b97e1c6c850b1a63bf6
Cr-Commit-Position: refs/heads/master@{#302704}

[ananta, 2014-11-04 00:39:41]

ananta@chromium.org changed reviewers:
+ scottmg@chromium.org, sky@chromium.org

[scottmg, 2014-11-04 00:45:45]

lgtm? I don't really understand the difference between the two values though, so
take that with a grain of salt.

[sky, 2014-11-04 03:27:13]

LGTM

[ananta, 2014-11-04 22:26:47]

The CQ bit was checked by ananta@chromium.org

[commit-bot: I haz the power, 2014-11-04 22:28:56]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/692803004/20001

[commit-bot: I haz the power, 2014-11-04 23:24:09]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2014-11-04 23:24:40]

Patchset 2 (id:??) landed as
https://crrev.com/a0b11455d6dcf2fd59df7b97e1c6c850b1a63bf6
Cr-Commit-Position: refs/heads/master@{#302704}