This unexpected behavior is causing problems for sites (see  issue 734106 ) and incompatible with most other implementations. Maybe we should require that sites that need a user gesture opt-in to the simulated click behavior (until we identify a permanent solution). The next origin trial would be a good time to change this behavior.

Is it possible to detect that the app is using or listening for the simulated click event while WebVR is presenting? If so, we could add a deprecation message* and/or UMA**.

* We would need to figure out what the solution will be and include it in the message.
** Even if we added it in M61, we probably wouldn't have time to act on it for M62. Authors would have time to respond, though.

Perhaps it is simpler and better to just handle it as part of the Origin Trial process. We still need to identify a solution for M62, though.

 Issue 734106  has been merged into this issue.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/09b107130f5c7a4cb377322b879ac2aac67cadbf

commit 09b107130f5c7a4cb377322b879ac2aac67cadbf
Author: Michael Thiessen <mthiesse@chromium.org>
Date: Tue Aug 22 04:58:14 2017

VR: Add gesture token to vrdisplayactivate, remove cardboard compat hack

This CL adds a gesture token to the displayactivate event which can only
be triggered by user action (on Android, placing the phone in a VR
headset and completing controller pairing while on a WebVR site).

This CL also removes the cardboard click event used for compatibility
and supplying user gesture, as a gesture is now supplied with the
displayactivate event.

Note: Once this lands, action will be required on the part of WebVR
Origin Trial participants that were previously relying on the cardboard
compat click events to act as user gestures - they will have to
perform any gesture-requiring actions in the displayactivate handler.

Bug:  716571 ,  756564 
Change-Id: I541c8e181fadaf58710da57b6e9f5e8971451073
Reviewed-on: https://chromium-review.googlesource.com/619170
Commit-Queue: Michael Thiessen <mthiesse@chromium.org>
Reviewed-by: Brandon Jones <bajones@chromium.org>
Cr-Commit-Position: refs/heads/master@{#496219}
[modify] https://crrev.com/09b107130f5c7a4cb377322b879ac2aac67cadbf/chrome/browser/android/vr_shell/vr_shell_gl.cc
[modify] https://crrev.com/09b107130f5c7a4cb377322b879ac2aac67cadbf/third_party/WebKit/Source/modules/vr/VRDisplay.cpp
[modify] https://crrev.com/09b107130f5c7a4cb377322b879ac2aac67cadbf/third_party/WebKit/Source/modules/vr/VRDisplay.h

For the record, I didn't totally remove the cardboard-compatible click event. It still fires for cardboard headsets, but won't fire for controller events.

If we want I can remove that too.

(Also removing cardboard click in https://chromium-review.googlesource.com/c/chromium/src/+/629263)

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/3320340b8edb9bb3e63cadeccf0a9effab3b06c6

commit 3320340b8edb9bb3e63cadeccf0a9effab3b06c6
Author: Michael Thiessen <mthiesse@chromium.org>
Date: Thu Aug 31 18:38:32 2017

VR: Disable cardboard click fallback and add gamepad tests.

TBR=dtrainor@chromium.org

Bug:  716571 
Change-Id: I8505ad125d8883a7a61dc202870d12227ebc3be5
Reviewed-on: https://chromium-review.googlesource.com/629263
Commit-Queue: Michael Thiessen <mthiesse@chromium.org>
Reviewed-by: David Trainor <dtrainor@chromium.org>
Reviewed-by: Brandon Jones <bajones@chromium.org>
Cr-Commit-Position: refs/heads/master@{#498929}
[modify] https://crrev.com/3320340b8edb9bb3e63cadeccf0a9effab3b06c6/chrome/android/BUILD.gn
[modify] https://crrev.com/3320340b8edb9bb3e63cadeccf0a9effab3b06c6/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellImpl.java
[modify] https://crrev.com/3320340b8edb9bb3e63cadeccf0a9effab3b06c6/chrome/android/javatests/src/org/chromium/chrome/browser/vr_shell/EmulatedVrController.java
[modify] https://crrev.com/3320340b8edb9bb3e63cadeccf0a9effab3b06c6/chrome/android/javatests/src/org/chromium/chrome/browser/vr_shell/WebVrInputTest.java
[delete] https://crrev.com/66da542bbad774a44e664dd37daba98bc85c40b7/chrome/android/javatests/src/org/chromium/chrome/browser/vr_shell/util/CardboardUtils.java
[modify] https://crrev.com/3320340b8edb9bb3e63cadeccf0a9effab3b06c6/chrome/android/shared_preference_files/test/vr_cardboard_skipdon_setupcomplete.json
[modify] https://crrev.com/3320340b8edb9bb3e63cadeccf0a9effab3b06c6/chrome/browser/android/vr_shell/vr_shell.cc
[modify] https://crrev.com/3320340b8edb9bb3e63cadeccf0a9effab3b06c6/chrome/browser/android/vr_shell/vr_shell.h
[modify] https://crrev.com/3320340b8edb9bb3e63cadeccf0a9effab3b06c6/chrome/browser/android/vr_shell/vr_shell_gl.cc
[modify] https://crrev.com/3320340b8edb9bb3e63cadeccf0a9effab3b06c6/chrome/browser/android/vr_shell/vr_shell_gl.h
[add] https://crrev.com/3320340b8edb9bb3e63cadeccf0a9effab3b06c6/chrome/test/data/android/webvr_instrumentation/html/test_gamepad_button.html
[rename] https://crrev.com/3320340b8edb9bb3e63cadeccf0a9effab3b06c6/chrome/test/data/android/webvr_instrumentation/html/test_screen_taps_not_registered.html
[delete] https://crrev.com/66da542bbad774a44e664dd37daba98bc85c40b7/chrome/test/data/android/webvr_instrumentation/html/test_screen_taps_registered.html
[modify] https://crrev.com/3320340b8edb9bb3e63cadeccf0a9effab3b06c6/device/vr/android/gvr/cardboard_gamepad_data_provider.h
[modify] https://crrev.com/3320340b8edb9bb3e63cadeccf0a9effab3b06c6/device/vr/android/gvr/gvr_gamepad_data_fetcher.cc
[modify] https://crrev.com/3320340b8edb9bb3e63cadeccf0a9effab3b06c6/device/vr/android/gvr/gvr_gamepad_data_provider.h