1581988 - Can't get vr display intermediately after relaunch VR process.

Status: VERIFIED FIXED

(Core :: WebVR, defect, P1)

Description

[Daosheng Mu[:daoshengmu]]

According to MozRegression, this bug happens at [1] in Bug 1566285. A regression from FF 70.

STR:

1. Open https://webvr.info/samples/04-simple-mirroring.html
2. Open another tab, go to Wikipedia
3. Close the first tab and wait VR process is shutdown.
4. Open another tab, go to https://webvr.info/samples/04-simple-mirroring.html.

Expected result:
We can get VR display and enter immersive mode successfully.

Actual result:
Can't get VR display.

[1] https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=0fb761cd8fa448eb511e8b2520ede5a3230853ed&tochange=b6d154b2309846531934289c1e167208fc385ac3

Comment 1

[Daosheng Mu[:daoshengmu]]

Attachment: Bug 1581988 - Making VR display enumerationCompleted be false when doing enumeration.

Comment 2

[Daosheng Mu[:daoshengmu]]

This is because VR process need to wait a little bit until it is launched, then we can get the current VR display states. Using mEnumerationCompleted should be a good way to go because it comes from the shmem from the other side.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/98238205f2a8
Making VR display enumerationCompleted be false when doing enumeration. r=kip

Comment 4

[Andreea Pavel [:apavel]]

https://hg.mozilla.org/mozilla-central/rev/98238205f2a8

Comment 5

[Daosheng Mu[:daoshengmu]]

Comment on attachment 9093463 [details]
Bug 1581988 - Making VR display enumerationCompleted be false when doing enumeration.

Beta/Release Uplift Approval Request

• User impact if declined: Users can't get VR display intermediately when reopening VR pages. (Fixes regress Bug 1566285)
• Is this code covered by automated tests?: No
• Has the fix been verified in Nightly?: Yes
• Needs manual test from QE?: No
• If yes, steps to reproduce:
• List of other uplifts needed: None
• Risk to taking this patch: Low
• Why is the change risky/not risky? (and alternatives if risky): This just resets the state of enumeration and ask for doing enumeration again, so it will not bring any risk.
• String changes made/needed:

Comment 6

[Pascal Chevrel:pascalc (PTO until April 26)]

Comment on attachment 9093463 [details]
Bug 1581988 - Making VR display enumerationCompleted be false when doing enumeration.

Fix for a VR regression introduced in 70, one liner, looks safe, uplift approved for 70 beta 9, Thanks.

Comment 7

[Alexandru Michis [:malexandru]]

https://hg.mozilla.org/releases/mozilla-beta/rev/8b150aa4228a

Comment 8

[Cristian Comorasu, QA [:ccomorasu], Releae Desktop QA - Please contact [e-mail]]

Sorry for the long pause.
I reproduced this issue on Fx 71.0a1(2019-09-17), using Windows 10 x64 with Oculus Rift.
I can confirm this issue is fixed, I verified on Fx 71.0a1 (2019-10-04) and Fx 70.0b12 on the same environment.