rebaseline_server: disable image magnifier, for huge UI speedup

rebaseline_server: disable image magnifier, for huge UI speedup

BUG=skia:2248
NOTREECHECKS=True
NOTRY=True
TBR=rmistry

Committed: http://code.google.com/p/skia/source/detail?r=13727

[epoger, 2014-03-10 19:10:47]

Running the "test circuit" in
https://goto.google.com/RebaselineServerQuickSpeedupVictories before and after
this change, with MAX_RECORDS=300 :

BEFORE:
T1=1222 ms, T2=1543 ms, T3=1077 ms, T4=22220 ms, T5=12157 ms 

AFTER:
T1=1199 ms, T2=1209 ms, T3=1367 ms, T4=1260 ms, T5=1822 ms


With a performance difference like that, the magnifier has to go immediately
IMO.  Then we can figure out how best to add it back in, in such a way that it
can be used for individual image pairs without slowing down all operations.

NOTREECHECKS=True
NOTRY=True
TBR=rmistry

[epoger, 2014-03-10 19:11:08]

committing TBR

[epoger, 2014-03-10 19:11:12]

The CQ bit was checked by epoger@google.com

[commit-bot: I haz the power, 2014-03-10 19:11:13]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-03-10 19:11:14]

No LGTM from a valid reviewer yet. Only full committers are accepted.
Even if an LGTM may have been provided, it was from a non-committer or
a lowly provisional committer, _not_ a full super star committer.
See http://www.chromium.org/getting-involved/become-a-committer
Note that this has nothing to do with OWNERS files.

[epoger, 2014-03-10 19:12:24]

The CQ bit was checked by epoger@google.com

[commit-bot: I haz the power, 2014-03-10 19:12:34]

CQ is trying da patch. Follow status at
https://skia-tree-status.appspot.com/cq/epoger@google.com/193073003/1

[commit-bot: I haz the power, 2014-03-10 19:12:56]

Change committed as 13727

[epoger, 2014-03-10 19:22:40]

Filed https://code.google.com/p/skia/issues/detail?id=2283 ('rebaseline_server:
re-enable image magnifier') to track followup work