Manually reverted https://chromium.googlesource.com/chromium/src/+/ccd5fbaca5867773830b38ea64c2a79f932f6478 and found it to be the cause.

Looks like erikchen went OOO for the rest of the week.

@piman, can you take a look? I think we should revert.

I'll go ahead and roll this out.

 Issue 624320  has been merged into this issue.

Please add a representative test story for this bug to src/content/test/gpu/page_sets/pixel_tests.py

All-righty, revert landed in https://crrev.com/a6429905f0b03788c5d6a4280f2a415c93e12c0b

Passing back to Erik for testing and re-landing.

Incoming pixel test added in crrev.com/2112603003.

Thanks for reverting. I think what's going on is that we schedule layers without images when it's only a background color, and I think that patch broke that.

 Issue 624221  has been merged into this issue.

https://codereview.chromium.org/2113443003/ should have the fix.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/ab056ef99dba995671df54dc97d738161cdc2188

commit ab056ef99dba995671df54dc97d738161cdc2188
Author: piman <piman@chromium.org>
Date: Thu Jun 30 05:15:51 2016

Reland: Remove unsafe cast from ImageTransportSurfaceOverlayMac::ScheduleCALayer.

Create an enum class Type in GLImage, which allows for safe downcasting.

BUG=619698, 624256 
CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_optional_gpu_tests_rel;tryserver.chromium.mac:mac_optional_gpu_tests_rel;tryserver.chromium.win:win_optional_gpu_tests_rel

Review-Url: https://codereview.chromium.org/2113443003
Cr-Commit-Position: refs/heads/master@{#403091}

[modify] https://crrev.com/ab056ef99dba995671df54dc97d738161cdc2188/gpu/ipc/service/image_transport_surface_overlay_mac.mm
[modify] https://crrev.com/ab056ef99dba995671df54dc97d738161cdc2188/ui/gl/gl_image.cc
[modify] https://crrev.com/ab056ef99dba995671df54dc97d738161cdc2188/ui/gl/gl_image.h
[modify] https://crrev.com/ab056ef99dba995671df54dc97d738161cdc2188/ui/gl/gl_image_io_surface.h
[modify] https://crrev.com/ab056ef99dba995671df54dc97d738161cdc2188/ui/gl/gl_image_io_surface.mm

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/8dcc2faa7b3d7a6c57f1c3a9492a132a4f2b9373

commit 8dcc2faa7b3d7a6c57f1c3a9492a132a4f2b9373
Author: vmiura <vmiura@chromium.org>
Date: Thu Jun 30 16:21:24 2016

Add pixel test for solid color backgrounds.

This catches issues with compositing solid color quads.
Test is initially expected to fail until reference images are generated.

R=kbr@chromium.org
BUG= 624256 
CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_optional_gpu_tests_rel;tryserver.chromium.mac:mac_optional_gpu_tests_rel;tryserver.chromium.win:win_optional_gpu_tests_rel

Review-Url: https://codereview.chromium.org/2112603003
Cr-Commit-Position: refs/heads/master@{#403193}

[modify] https://crrev.com/8dcc2faa7b3d7a6c57f1c3a9492a132a4f2b9373/content/test/data/gpu/pixel_background.html
[modify] https://crrev.com/8dcc2faa7b3d7a6c57f1c3a9492a132a4f2b9373/content/test/gpu/gpu_tests/pixel_expectations.py
[modify] https://crrev.com/8dcc2faa7b3d7a6c57f1c3a9492a132a4f2b9373/content/test/gpu/page_sets/gpu_rasterization_tests.py
[modify] https://crrev.com/8dcc2faa7b3d7a6c57f1c3a9492a132a4f2b9373/content/test/gpu/page_sets/pixel_tests.py

Issue 624723 has been merged into this issue.

 Issue 624336  has been merged into this issue.

Erik is on vacation. Can someone else pick this up so we can roll back?

Already handled by piman@.  Thanks

I have tested chrome#53.0.2783.5 with the above revert (per c#9) and below are the observations.
1. Still seeing rendering issue (White block) on youtube videos. This is not 100% consistent like previous chrome however the repro possibility is 3/10 (Ref issue: https://bugs.chromium.org/p/chromium/issues/detail?id=624320)
2. This issue (https://bugs.chromium.org/p/chromium/issues/detail?id=624336) is completely fixed.

Thank you!

 Issue 624675  has been merged into this issue.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/64b487795003572d5769667515d68b46857ae2c5

commit 64b487795003572d5769667515d68b46857ae2c5
Author: vmiura <vmiura@chromium.org>
Date: Fri Jul 01 23:52:10 2016

Update GPU pixel test expectations.

New tests are rebaselined and suppresions can now be removed.

R=kbr@chromium.org
BUG= 624256 
CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_optional_gpu_tests_rel;tryserver.chromium.mac:mac_optional_gpu_tests_rel;tryserver.chromium.win:win_optional_gpu_tests_rel

Review-Url: https://codereview.chromium.org/2113073003
Cr-Commit-Position: refs/heads/master@{#403566}

[modify] https://crrev.com/64b487795003572d5769667515d68b46857ae2c5/content/test/gpu/gpu_tests/pixel_expectations.py

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/3c0d640779d29ebbc4853ccd148f538434c50e9c

commit 3c0d640779d29ebbc4853ccd148f538434c50e9c
Author: cwallez <cwallez@chromium.org>
Date: Mon Jul 04 17:11:26 2016

Add GPU pixel test expectations

Add suppressions for tests that started failing after
64b487795003572d5769667515d68b46857ae2c5

BUG= 624256 
TBR=kbr@chromium.org
CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_optional_gpu_tests_rel;tryserver.chromium.mac:mac_optional_gpu_tests_rel;tryserver.chromium.win:win_optional_gpu_tests_rel

Review-Url: https://codereview.chromium.org/2119213002
Cr-Commit-Position: refs/heads/master@{#403697}

[modify] https://crrev.com/3c0d640779d29ebbc4853ccd148f538434c50e9c/content/test/gpu/gpu_tests/pixel_expectations.py

broken again on Mac 54.0.2787.0 

How do we keep breaking this and not catching it before it gets committed?

> How do we keep breaking this and not catching it before it gets committed?

Sorry OOO till 7/18.  Chris could you take a look?

The test got reverted in #25.  cwallez@, do you have more information on the Pixel.SolidColorBackground failures?

This was a nasty sequence of events
* r403193 added this test, but it was suppressed so that a baseline could be added
* r403424 broke this again (this was a merge conflict I should have caught)
* r403566 removed suppressions, but it was already broken in the mean time

So, I think that this is fixed and shouldn't be break-able anymore. I'll remove the suppression and try to commit a CL that breaks it, to be certain.

Thanks Chris, I don't want us to lose users on canary if we make big apps break, so great to fix this quickly.

 Issue 625482  has been merged into this issue.

Verified the issue on M53# 53.0.2785.8 on Mac OS X 10.11.5 and is working as intended.
Attaching a screenshot for reference. Also adding TE-Verified labels.
Thank You.

 Issue 625409  has been merged into this issue.

Based on offline chat with  ccameron@ and verified the fix on latest Chrome Dev i.e., 53.0.2785.8(As well in comment#32). Marking the bug as Fixed.