re-land r7258 with fixes and tests

re-land r7258 with fixes and tests
BUG=http://code.google.com/p/skia/issues/detail?id=1079
TBR=reed
Committed: https://code.google.com/p/skia/source/detail?r=7291

[epoger, 2013-01-19 01:22:32]

patchset 1 just re-lands r7258; now to make it work better...

[epoger, 2013-01-19 04:21:02]

I'm going to go ahead and commit this, so that development in gmmain.cpp can
keep moving forward in my absence next week.

I am confident that it won't break anything, based on the addition of the new
tests, but certainly feel free to roll it out if it seems problematic.

Review tips:

Patch Set 1 just re-lands r7258.  Nothing new to review there.

Patch Set 2 adds new tests that failed (but succeeded as of r7257)

Patch Set 3 fixes the problem with a small change to just one file, gmmain.cpp. 
You can see just that change at
https://codereview.appspot.com/7132060/diff2/3001:13001/gm/gmmain.cpp .

[epoger, 2013-01-19 05:43:17]

This CL caused a couple of new failures, which I fixed in
https://codereview.appspot.com/7129057 .