Apps' drawing may hang when switching between them.

Close for FF 6.0.4 and GG 7.0.0

Most probably, the https://lf-automotivelinux.atlassian.net/browse/SPEC-1995 is related to this issue. The difference is in the backends used, but I think it doesn't matter.

The solution was to make GLSurfaceWayland (used with in-process-gpu mode) to use wl_surface_frame, which made it to wait a callback from the compositor to send new frames.

https://github.com/webosose/chromium68/pull/10

The error is a typical scenario of gpu thread hang that causes eventually app launching to hang too (and any other call for gpu process host).

After further examination we found that the gpu thread hangs in eglSwapBuffers call. And we observed that, when an app is sent to background, eglSwapBuffer hangs. If we reopen that application, then the call will finish and it will continue rendering.

But in the scenario where we open a different application, that eglSwapBuffers call will*not* finish. Then the second app hangs trying to connect to gpu thread through gpu process host initialization.

This scenario happens when we are emiting frames while we send an application offscreen (i.e. playing video or a css animation can get you to this scenario).

We have added resume/suspend support, but the issue is still there.

Looks like a browser process waits for a connection with the gpu, but it's hang. Check thread 1 and 15.