Dump stack traces to syslog when rendering fails.

Change-Id: I970194e094b61664f979fb89aaebe3d1bb311c8d
Use FAKESTYLES for FreeSerif.

The FreeSerif bold and italic fonts don't have as broad coverage as the
main FreeSerif font.  So use FAKESTYLES which synthesizes fake boldface
and italics fonts from the main font.  Quality of the font goes down
for headings, etc.  Sigh.  But it means that we don't get question
marks in Tamil, etc.

Bug: 28206
Change-Id: Ic543fe6c5544c79cd155404342f126e6641103b2
Don't crash if the collection title looks like a URL.

Change-Id: Idb451a393d1376b79811ffaef907c179c0edda20