In gm, install drawFilter for pipe and tiledPipe.

In gm, install drawFilter for pipe and tiledPipe.

Fixes bugs in drawing un-antialiased text in gm.

Committed: https://code.google.com/p/skia/source/detail?r=8173

[epoger, 2013-03-15 15:27:16]

LGTM

https://codereview.chromium.org/12812016/diff/1/gm/gmmain.cpp
File gm/gmmain.cpp (right):

https://codereview.chromium.org/12812016/diff/1/gm/gmmain.cpp#newcode904
gm/gmmain.cpp:904: installFilter(&canvas);
As discussed in
https://codereview.chromium.org/12632015/diff/1006/gm/gmmain.cpp#newcode898 , it
disturbs me that this error went unnoticed, and ideally
this fix would be accompanied by self-test improvements that exercise it and
related behavior.

It can be pretty frustrating when our tools don't detect regressions... that's
why I've been adding self-tests to exercise all new gm behavior.  But that does
take time away from other work, so it's a balancing act.

[scroggo, 2013-03-15 15:29:12]

Committed patchset #1 manually as r8173 (presubmit successful).