GitLab

The original patch and the previous relands broke
WebRtcWebcamBrowserTests/WebRtcWebcamBrowserTest.MANUAL_TestAcquiringAndReacquiringWebcam/0
in the WebRtc Mac-tester bots, which run using a Logitech C920.

The root cause was that for resolutions >= 1280x720p, the code
configures the use of MJPEG encoding, and that seems to produce
partially invalid JPEG markers, e.g.
(Corrupt JPEG data: 10 extraneous bytes before marker 0xd4)
that throw the AVCaptureStillImageOutput off.

This CL disconnects |stillImageOutput_| in this case.

Original description ----------------------------------------------
ImageCapture: Implement takePhoto() for Mac AVFoundation

By pulling the necessary symbols out of AVFoundation
and using them; most notably (Cr)AVCaptureStillImageOutput.

TakePhoto is already implemented for Android (both APIs).

Also adding VideoCaptureDeviceTest::MAYBE_TakePhoto
test case, enabled only for Mac.

BUG=518807
TEST=Run build with flag --enable-blink-features=ImageCapture,
navigate to [1] and push buttons
- Open Camera ...
- Create ImageCapturer
- takePhoto()  (N times!) --> profit

[1] https://rawgit.com/Miguelao/demos/master/imagecapture.html

TBR=rsesek@chromium.org since the change is trivial.

Review-Url: https://codereview.chromium.org/2155723002
Cr-Commit-Position: refs/heads/master@{#405889}