Chrome Version:
FAIL: Mac 10.11, Chrome 59.0.3071.82, FP 26.0.0.120
FAIL: Mac 10.11, Chrome 59.0.3071.82, FP 21.0.0.242
FAIL: MacOS 10.12.5, Chrome Version 58.0.3029.110 (64-bit), Flash Player 25.0.0.171
PASS: Mac 10.11. FF
PASS: Mac 10.11, Safari
PASS: Windows 7 x64, Chrome 59.0.3071.82, FP 26.0.0.120
PASS: Windows 7 x64, FF
PASS: Windows 7 x64, IE

Method:
http://www.sonypictures.com/movies/district9/
1. Open above URL on Mac 10.11 in Chrome browser.
2. Click Full screen button for the loaded video.

Result:
Nothing happens, the video does not display in Full screen.
Notice that user must click on the Full screen button second time to get the video in Full screen. The Full screen button will work until the user closes and reopens the browser. Then he/she needs to click on the button two time to display the video in Full screen mode.

Expected:
Fullscreen should work from the first click.

Workaround:
None 

Developer analysis: 

Normally when Flash Player enters into fullscreen mode, Chrome will call PPAPI |nstance::DidChangeView()| to inform Pepper plugin that fullscreen state has been changed, and when user exits fullscreen mode, Chrome will also call PPAPI |nstance::DidChangeView()| to inform Pepper plugin about the current fullscreen state.
In this test scenario, when user clicks fullscreen mode button, Chrome enters fullscreen and exits immediately, and from Pepper flash point of view, it never receives the notification through |Instance::DidChangeView()| saying that Chrome has entered fullscreen mode, so Flash does not think it ever enters fullscreen.
Since this entering/exiting fullscreen actions all happened within Chrome without Pepper flash's interaction, we believe this is Chrome's issue.