Remove some LatencyInfo merging code path

Remove some LatencyInfo merging code path

This CL removes a few code paths that do LatencyInfo merging:
1. compositor -> output surface through CompositorFrameMetadata
2. gpu -> browser compositor through
GpuHostMsg_AcceleratedSurfaceBuffersSwapped_Params and
GpuHostMsg_AcceleratedSurfacePostSubBuffer_Param

A follow up CL will remove GPU side LatencyInfo merging (mainly in image
transport surface) so that we remove LatencyInfo merging entirely from
the code path renderer cc -> gpu -> browser cc -> gpu.

BUG=246034
TEST=unittests pass.

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=242825

[Yufeng Shen (Slow to review), 2013-12-20 19:07:20]

This is another small part of the overall effort of removing
LatencyInfo merging. Though it has several TODOs, they make
the CL small enough for easy review.

I would like 
jbauman@ to have a review of the overall change, and  
danakj@ for OWNER review of cc/*
kbr@  for OWNER review of content/*

[danakj, 2013-12-20 19:25:32]

LGTM

[danakj, 2013-12-20 19:27:37]

https://codereview.chromium.org/100443006/diff/1/content/browser/aura/softwar...
File content/browser/aura/software_browser_compositor_output_surface.cc (right):

https://codereview.chromium.org/100443006/diff/1/content/browser/aura/softwar...
content/browser/aura/software_browser_compositor_output_surface.cc:39: // take
std::vector<ui::LatencyInfo> directly so we only post the task once.
One question here, should we merge the LatencyInfo here and post once instead of
posting a bunch of times? That seems like it would match the expectations of the
old code which isn't transitioned yet. Not a big deal either way probably?

[Yufeng Shen (Slow to review), 2013-12-20 19:36:31]

https://codereview.chromium.org/100443006/diff/1/content/browser/aura/softwar...
File content/browser/aura/software_browser_compositor_output_surface.cc (right):

https://codereview.chromium.org/100443006/diff/1/content/browser/aura/softwar...
content/browser/aura/software_browser_compositor_output_surface.cc:39: // take
std::vector<ui::LatencyInfo> directly so we only post the task once.
On 2013/12/20 19:27:37, danakj wrote:
> One question here, should we merge the LatencyInfo here and post once instead
of
> posting a bunch of times? That seems like it would match the expectations of
the
> old code which isn't transitioned yet. Not a big deal either way probably?

It depends on what CompositorFrameDrawn() does with the the LatencyInfo.
CompositorFrameDrawn() does UMA/Telemetry metrics computation on the
LatencyInfo, which is broken currently anyway while I am doing the overhaul, so
it does not really matter.

[Ken Russell (switch to Gerrit), 2013-12-20 22:58:33]

Has the window snapshot code (for example, Telemetry's testScreenshotSync test
in tab_unittest.py) been tested with these changes, and is it known to still
work correctly?

[Ken Russell (switch to Gerrit), 2013-12-20 22:58:57]

Also, FWIW, you'll need more reviewers for the content/ changes; I'm not an
owner there, only in renderer_host.

[Yufeng Shen (Slow to review), 2013-12-23 17:46:53]

On 2013/12/20 22:58:33, Ken Russell wrote:
> Has the window snapshot code (for example, Telemetry's testScreenshotSync test
> in tab_unittest.py) been tested with these changes, and is it known to still
> work correctly?

Yes, I checked that 
src/tools/telemetry$ ./run_tests --browser=cros-chrome --remote=XXX
GpuTabTest.testScreenshot
still pass on Pixel.

[Yufeng Shen (Slow to review), 2013-12-23 17:48:36]

On 2013/12/20 22:58:57, Ken Russell wrote:
> Also, FWIW, you'll need more reviewers for the content/ changes; I'm not an
> owner there, only in renderer_host.

ahh, I saw you are also OWNER of content/common/gpu/ ?

Dana covered cc/ and content/browser/aura/   so I thought you cover the rest.

[Ken Russell (switch to Gerrit), 2013-12-23 21:54:40]

Right, I'd forgotten that I was an owner of that directory.

LGTM

[commit-bot: I haz the power, 2014-01-02 16:49:09]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/miletus@chromium.org/100443006/1

[commit-bot: I haz the power, 2014-01-02 18:36:58]

Retried try job too often on android_aosp for step(s) compile
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=android_ao...

[commit-bot: I haz the power, 2014-01-02 19:07:15]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/miletus@chromium.org/100443006/430001

[commit-bot: I haz the power, 2014-01-02 22:56:52]

Change committed as 242825