Add full screen mode feature for 2D browsing

[haanhvu]

This commit adds a Fullscreen item in the hamburger menu to set the current window in the fullscreen mode. The commit also enables three edge cases:

• When users sets fullscreen mode, go into a fullscreen video, exit fullscreen video, the fullscreen mode is reserved.
• When users sets fullscreen mode, opens a new tab, that tab is opened in fullscreen mode too.
• When exitFullScreenMode() is called (e.g., in onPause()), fullscreen mode is exited correctly.

Fixes #1494

[svillar]

Seems a nice feature, however I am not sure it's polished enough. At least I found weird the following scenarios

1. put the browser in fullscreen
2. goto youtube.com and select a video
3. in the video player click on fullscreen
4. exit fullscreen

When you exit fullscreen the browser goes back to the unfullscreen mode again. I don't think that's neccesarily bad, but the addition of this feature makes the navigation confusing, it's like the fullscreen mode you had previously selected was "forgotten". In the current code, it's crystal clear, the window goes fullscreen only when the page requests it (after a user gesture of course).

Another example is when after clicking on a link the page opens another tab. In that case the window un-fullscreens automatically as well, giving the impression that the feature no longer works.

I am not really sure what to do. Maybe @felipeerias has further thoughts about how the UI interaction should work in this case but I think it's really tricky if we want to make it work properly.

Apart from that the commit message should be changed. In general it should follow this template:

Brief description/Title

Detailed description

Fixes #0000

[haanhvu]

Seems a nice feature, however I am not sure it's polished enough. At least I found weird the following scenarios

1. put the browser in fullscreen
2. goto youtube.com and select a video
3. in the video player click on fullscreen
4. exit fullscreen

When you exit fullscreen the browser goes back to the unfullscreen mode again. I don't think that's neccesarily bad, but the addition of this feature makes the navigation confusing, it's like the fullscreen mode you had previously selected was "forgotten". In the current code, it's crystal clear, the window goes fullscreen only when the page requests it (after a user gesture of course).

Another example is when after clicking on a link the page opens another tab. In that case the window un-fullscreens automatically as well, giving the impression that the feature no longer works.

I am not really sure what to do. Maybe @felipeerias has further thoughts about how the UI interaction should work in this case but I think it's really tricky if we want to make it work properly.

Apart from that the commit message should be changed. In general it should follow this template:

Brief description/Title

Detailed description

Fixes #0000

Yeah these scenarios seems worth solving. I have been working on them.

Another scenario that seems worth solving is when activity pauses. Currently in onPause() we exit fullscreen video, so I think we shoudl exit fullscreen mode too.

[haanhvu]

Seems a nice feature, however I am not sure it's polished enough. At least I found weird the following scenarios

1. put the browser in fullscreen
2. goto youtube.com and select a video
3. in the video player click on fullscreen
4. exit fullscreen

When you exit fullscreen the browser goes back to the unfullscreen mode again. I don't think that's neccesarily bad, but the addition of this feature makes the navigation confusing, it's like the fullscreen mode you had previously selected was "forgotten". In the current code, it's crystal clear, the window goes fullscreen only when the page requests it (after a user gesture of course).
Another example is when after clicking on a link the page opens another tab. In that case the window un-fullscreens automatically as well, giving the impression that the feature no longer works.
I am not really sure what to do. Maybe @felipeerias has further thoughts about how the UI interaction should work in this case but I think it's really tricky if we want to make it work properly.
Apart from that the commit message should be changed. In general it should follow this template:

Brief description/Title

Detailed description

Fixes #0000

Yeah these scenarios seems worth solving. I have been working on them.

Another scenario that seems worth solving is when activity pauses. Currently in onPause() we exit fullscreen video, so I think we shoudl exit fullscreen mode too.

I have fixed all these three edge cases, as I described in the commit message. Not sure if I handled them smoothly enough, but I think we can improve from the current change if we want.