Update gpu trace marker system for MultiDrawBuffer world

Update gpu trace marker system for MultiDrawBuffer world

The main thrust of this CL is to remove the currCmdMarker variable from GrTargetCommands::flush. In a MultiDrawBuffer world the Cmds need not be execute in the order of their issuance.

Committed: https://skia.googlesource.com/skia/+/bca3c9fb2d5c043985b878633e9630cf12e04bd6

[robertphillips, 2015-03-05 15:35:47]

robertphillips@google.com changed reviewers:
+ egdaniel@google.com

[robertphillips, 2015-03-05 16:59:46]

Updated for https://codereview.chromium.org/981973002/ (Fix GPU trace marker
bug) and successfully tested.

[robertphillips, 2015-03-05 17:00:33]

The CQ bit was checked by robertphillips@google.com

[commit-bot: I haz the power, 2015-03-05 17:01:44]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/978363002/60001

[commit-bot: I haz the power, 2015-03-05 17:01:44]

Note for Reviewers:
The CQ is waiting for an approval.
If you believe that the CL is not ready yet, or if you would like to L-G-T-M
with comments then please uncheck the CQ checkbox.

Waiting for LGTM from valid reviewer(s) till 2015-03-05 23:01 UTC

[egdaniel, 2015-03-05 17:03:58]

lgtm

[commit-bot: I haz the power, 2015-03-05 17:17:20]

Committed patchset #4 (id:60001) as
https://skia.googlesource.com/skia/+/bca3c9fb2d5c043985b878633e9630cf12e04bd6