Revert of Re-land WebVR compositor bypass via BrowserMain context + mailbox

Revert of Re-land WebVR compositor bypass via BrowserMain context + mailbox (patchset #37 id:710001 of https://codereview.chromium.org/2729523002/ )

Reason for revert:
Layout tests still failing for mac and windows despite passing on the trybots. Example: https://build.chromium.org/p/chromium.webkit/buildstatus?builder=WebKit%20Mac10.9&number=43627

Original issue's description:
> Re-land WebVR compositor bypass via BrowserMain context + mailbox
> 
> Implement compositor bypass for WebVR via mailbox copy:
> 
> - Create a GPU command buffer GL context in the VrShellGl thread that's
>   backed by a native Surface. This is encapsulated inside the new 
>   MailboxToSurfaceBridge class.
> 
> - WebKit's VRDisplay sends a MailboxHolder for each frame (as drawn
>   via WebGL on the GPU process) as argument to the SubmitFrame mojo
>   call.
> 
> - MailboxToSurfaceLayerBridge uses its GPU command buffer GL context
>   to draw the mailbox content to a Surface.
> 
> - VrShellGl picks up the frame from the corresponding SurfaceTexture
>   and  proceeds with rendering as usual with its native GL context
>   as needed for the low-level GVR API.
> 
> Also implements on-the-fly canvas resizing, the transfer surface and
> GVR renderbuffer are resized as needed to match the source canvas.
> 
> Added frame number as an argument to various TRACE_EVENTs for timing
> analysis.
> 
> It includes two separate modes for frame scheduling, the more
> aggressive one is conditional on
> chrome:://flags#enable-webvr-experimental-rendering since the
> framerate seems a bit less stable.
> 
> BUG=698643
> CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.android:android_optional_gpu_tests_rel;master.tryserver.chromium.linux:closure_compilation;master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel
> 
> Review-Url: https://codereview.chromium.org/2729523002
> Cr-Original-Commit-Position: refs/heads/master@{#455592}
> Committed: https://chromium.googlesource.com/chromium/src/+/6280ec5b6e3b4c307926eb1bf0167acc2a0d4a74
> Review-Url: https://codereview.chromium.org/2729523002
> Cr-Commit-Position: refs/heads/master@{#456130}
> Committed: https://chromium.googlesource.com/chromium/src/+/9f86464794416e81abfe5921e9fac892716c610b

TBR=mthiesse@chromium.org,bajones@chromium.org,khushalsagar@chromium.org,dcheng@chromium.org,piman@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=698643
Review-Url: https://codereview.chromium.org/2742083002
Cr-Commit-Position: refs/heads/master@{#456164}
Committed: https://chromium.googlesource.com/chromium/src/+/587f430144e9a2ad778649dff1c297b09977c2a3

[klausw, 2017-03-10 20:46:41]

The CQ bit was checked by klausw@chromium.org

[klausw, 2017-03-10 20:46:42]

Created Revert of Re-land WebVR compositor bypass via BrowserMain context +
mailbox

[commit-bot: I haz the power, 2017-03-10 20:47:28]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-03-10 20:47:29]

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

[commit-bot: I haz the power, 2017-03-10 20:47:30]

No L-G-T-M from a valid reviewer yet. 
CQ run can only be started by full committers or once the patch has
received an L-G-T-M from a full committer.
Even if an L-G-T-M may have been provided, it was from a non-committer,
_not_ a full super star committer.
Committers are members of the group "project-chromium-committers".
Note that this has nothing to do with OWNERS files.

[ddorwin, 2017-03-10 21:13:45]

ddorwin@chromium.org changed reviewers:
+ ddorwin@chromium.org

[ddorwin, 2017-03-10 21:13:46]

The CQ bit was checked by ddorwin@chromium.org

[ddorwin, 2017-03-10 21:13:46]

lgtm

[commit-bot: I haz the power, 2017-03-10 21:14:23]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-03-10 21:15:51]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1489180426070960, "parent_rev":
"203654f1cb443b997c58dfda0dbb8e11d7222f97", "commit_rev":
"587f430144e9a2ad778649dff1c297b09977c2a3"}

[commit-bot: I haz the power, 2017-03-10 21:16:42]

Description was changed from

==========
Revert of Re-land WebVR compositor bypass via BrowserMain context + mailbox
(patchset #37 id:710001 of https://codereview.chromium.org/2729523002/ )

Reason for revert:
Layout tests still failing for mac and windows despite passing on the trybots.
Example:
https://build.chromium.org/p/chromium.webkit/buildstatus?builder=WebKit%20Mac...

Original issue's description:
> Re-land WebVR compositor bypass via BrowserMain context + mailbox
> 
> Implement compositor bypass for WebVR via mailbox copy:
> 
> - Create a GPU command buffer GL context in the VrShellGl thread that's
>   backed by a native Surface. This is encapsulated inside the new 
>   MailboxToSurfaceBridge class.
> 
> - WebKit's VRDisplay sends a MailboxHolder for each frame (as drawn
>   via WebGL on the GPU process) as argument to the SubmitFrame mojo
>   call.
> 
> - MailboxToSurfaceLayerBridge uses its GPU command buffer GL context
>   to draw the mailbox content to a Surface.
> 
> - VrShellGl picks up the frame from the corresponding SurfaceTexture
>   and  proceeds with rendering as usual with its native GL context
>   as needed for the low-level GVR API.
> 
> Also implements on-the-fly canvas resizing, the transfer surface and
> GVR renderbuffer are resized as needed to match the source canvas.
> 
> Added frame number as an argument to various TRACE_EVENTs for timing
> analysis.
> 
> It includes two separate modes for frame scheduling, the more
> aggressive one is conditional on
> chrome:://flags#enable-webvr-experimental-rendering since the
> framerate seems a bit less stable.
> 
> BUG=698643
>
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.android:android_optional_gpu_tests_rel;master.tryserver.chromium.linux:closure_compilation;master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel
> 
> Review-Url: https://codereview.chromium.org/2729523002
> Cr-Original-Commit-Position: refs/heads/master@{#455592}
> Committed:
https://chromium.googlesource.com/chromium/src/+/6280ec5b6e3b4c307926eb1bf016...
> Review-Url: https://codereview.chromium.org/2729523002
> Cr-Commit-Position: refs/heads/master@{#456130}
> Committed:
https://chromium.googlesource.com/chromium/src/+/9f86464794416e81abfe5921e9fa...

TBR=mthiesse@chromium.org,bajones@chromium.org,khushalsagar@chromium.org,dche...
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=698643
==========

to

==========
Revert of Re-land WebVR compositor bypass via BrowserMain context + mailbox
(patchset #37 id:710001 of https://codereview.chromium.org/2729523002/ )

Reason for revert:
Layout tests still failing for mac and windows despite passing on the trybots.
Example:
https://build.chromium.org/p/chromium.webkit/buildstatus?builder=WebKit%20Mac...

Original issue's description:
> Re-land WebVR compositor bypass via BrowserMain context + mailbox
> 
> Implement compositor bypass for WebVR via mailbox copy:
> 
> - Create a GPU command buffer GL context in the VrShellGl thread that's
>   backed by a native Surface. This is encapsulated inside the new 
>   MailboxToSurfaceBridge class.
> 
> - WebKit's VRDisplay sends a MailboxHolder for each frame (as drawn
>   via WebGL on the GPU process) as argument to the SubmitFrame mojo
>   call.
> 
> - MailboxToSurfaceLayerBridge uses its GPU command buffer GL context
>   to draw the mailbox content to a Surface.
> 
> - VrShellGl picks up the frame from the corresponding SurfaceTexture
>   and  proceeds with rendering as usual with its native GL context
>   as needed for the low-level GVR API.
> 
> Also implements on-the-fly canvas resizing, the transfer surface and
> GVR renderbuffer are resized as needed to match the source canvas.
> 
> Added frame number as an argument to various TRACE_EVENTs for timing
> analysis.
> 
> It includes two separate modes for frame scheduling, the more
> aggressive one is conditional on
> chrome:://flags#enable-webvr-experimental-rendering since the
> framerate seems a bit less stable.
> 
> BUG=698643
>
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.android:android_optional_gpu_tests_rel;master.tryserver.chromium.linux:closure_compilation;master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel
> 
> Review-Url: https://codereview.chromium.org/2729523002
> Cr-Original-Commit-Position: refs/heads/master@{#455592}
> Committed:
https://chromium.googlesource.com/chromium/src/+/6280ec5b6e3b4c307926eb1bf016...
> Review-Url: https://codereview.chromium.org/2729523002
> Cr-Commit-Position: refs/heads/master@{#456130}
> Committed:
https://chromium.googlesource.com/chromium/src/+/9f86464794416e81abfe5921e9fa...

TBR=mthiesse@chromium.org,bajones@chromium.org,khushalsagar@chromium.org,dche...
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=698643

Review-Url: https://codereview.chromium.org/2742083002
Cr-Commit-Position: refs/heads/master@{#456164}
Committed:
https://chromium.googlesource.com/chromium/src/+/587f430144e9a2ad778649dff1c2...
==========

[commit-bot: I haz the power, 2017-03-10 21:16:43]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/587f430144e9a2ad778649dff1c2...