DM: don't run rtree when kSkipTiled is set.

Follow up to http://crrev.com/165723009, which changed this in GM.

Tested: out/Debug/dm

BUG=skia:

Committed: http://code.google.com/p/skia/source/detail?r=13537

NOTREECHECKS=True
NOTRY=True
R=scroggo@google.com, senorblanco@google.com, mtklein@google.com

Author: mtklein@chromium.org

Review URL: https://codereview.chromium.org/175283002

git-svn-id: http://skia.googlecode.com/svn/trunk@13540 2bbb7eff-a529-9590-31e7-b0007b416f81
1 file changed