Measure picture recording speed in nanobench.

Measure picture recording speed in nanobench.

Today we measure SkPicture playback speed, but not the time it takes to record
the SkPicture.  This fixes that by reading SKPs from disk and re-recording them.

On the console, recording shows up first as the nonrendering skp benches,
followed later by the usual playback benches:

maxrss  loops   min median  mean    max stddev  samples     config  bench
51M  2   165µs   168µs   169µs   178µs   3%  ▆▄▃█▂▄▁▂▁▁  nonrendering    tabl_slashdot.skp
57M  1   9.72ms  9.77ms  9.79ms  9.97ms  1%  █▂▂▅▃▂▁▄▂▁  nonrendering    desk_pokemonwiki.skp
57M  32  2.92µs  2.96µs  3.03µs  3.46µs  6%  ▅▁▁▁▁▁▁█▂▁  nonrendering    desk_yahoosports.skp
...
147M 1   3.86ms  3.87ms  3.97ms  4.81ms  7%  █▁▁▁▁▁▁▁▁▁  8888    tabl_slashdot.skp_1
147M 1   4.54ms  4.56ms  4.55ms  4.56ms  0%  █▅▇▅█▅▂▁▅▁  565     tabl_slashdot.skp_1
147M 2   3.08ms  3.24ms  4.17ms  8.18ms  50% █▁▁█▁▁▁▁▁▁  gpu     tabl_slashdot.skp_1
147M 1   1.61ms  1.62ms  1.69ms  2.33ms  13% █▁▁▁▁▁▁▁▁▁  8888    desk_pokemonwiki.skp_1
147M 1   1.44ms  1.44ms  1.45ms  1.47ms  1%  ▅▂█▂▂▅▁▁▂▁  565     desk_pokemonwiki.skp_1
...

On skiaperf.com, they'll also be separated out from playback benches by bench_type.

BUG=skia:

Committed: https://skia.googlesource.com/skia/+/fd731ce804cd3223318f3feee2c98404890b65f2

[mtklein, 2014-09-10 17:39:56]

mtklein@google.com changed reviewers:
+ mtklein@google.com, reed@google.com

[mtklein, 2014-09-10 17:53:33]

mtklein@google.com changed reviewers:
+ jcgregorio@google.com

[mtklein, 2014-09-10 17:53:33]

Joe's reminded me skiaperf.com will be better if we don't pun source_type.  I've
added bench_type.

[jcgregorio, 2014-09-10 18:12:26]

On 2014/09/10 17:53:33, mtklein wrote:
> Joe's reminded me http://skiaperf.com will be better if we don't pun
source_type.  I've
> added bench_type.

LGTM

[reed1, 2014-09-10 18:58:19]

lgtm

[reed1, 2014-09-10 18:58:27]

The CQ bit was checked by reed@google.com

[commit-bot: I haz the power, 2014-09-10 18:59:30]

CQ is trying da patch. Follow status at
 https://skia-tree-status.appspot.com/cq/mtklein@chromium.org/559153002/40001

[mtklein, 2014-09-10 19:10:10]

The CQ bit was checked by mtklein@google.com

[commit-bot: I haz the power, 2014-09-10 19:11:15]

CQ is trying da patch. Follow status at
 https://skia-tree-status.appspot.com/cq/mtklein@chromium.org/559153002/80001

[commit-bot: I haz the power, 2014-09-10 19:19:35]

Committed patchset #5 (id:80001) as fd731ce804cd3223318f3feee2c98404890b65f2