(bug 44895) Gerrit commit message font is too small

The commit message shown on change pages is a bit too small. It is set
upstream at a size of 8pt.  Raising the size by 1pt to 9pt would make it
easier to the eyes of old people.

Change-Id: I6b213f7b095745d0629b8b1fadf8f433a074f9c2
Merge "(bug 44895) Gerrit commit message font is too small" into production