[PDF] Fix printing crashes caused by font streams that don't support
getMemoryBase().

An apparently recently change started putting web fonts into SkStream objects
that don't support getMemoryBase().  This change uses writeStream to avoid
needing to call getMemoryBase().

cherry-pick of https://code.google.com/p/skia/source/detail?r=10918

bug:10461655
Change-Id: Ic383c3b4ce9002063062775c769acf12b5ee13f5
1 file changed