Previously, we'd minimize fullscreen windows (if
SDL_HINT_VIDEO_MINIMIZE_ON_FOCUS_LOSS was set) during SDL_DestroyWindow if they
had keyboard focus, because we call SDL_SetKeyboardFocus(NULL) which yields a
OnWindowsFocusLost event.
Related to https://bugzilla.libsdl.org/show_bug.cgi?id=1840
SDL 2.x recently accepted patches to enable OpenGL ES 2 support via Google's ANGLE library. The thought is to try to eventually merge SDL/WinRT's OpenGL code with SDL-official's.
Based on the original port to Wayland by: Joel Teichroeb, Benjamin Franzke, Scott Moreau, et al.
Additional changes in this commit, done by me:
* Wayland uses the common EGL framework
* EGL can now create a desktop OpenGL context
* testgl2 loads GL functions dynamically, no need to link to libGL anymore
* Assorted fixes to the Wayland backend
Tested on the Weston Compositor (v1.0.5) that ships with Ubuntu 13.10,
running Weston under X. Tests ran: testrendercopyex (all backends), testgl2, testgles2,testintersections
If the app is in landscape mode and the user presses the power button, a pause
is followed immediately by a surfaceChanged event because the lock screen
is shown in portrait mode. This triggers a "false" resume.
So, we just pause and resume following the onWindowFocusChanged events.
Also, wait for SDL_APP_WILLENTERBACKGROUND and SDL_APP_DIDENTERBACKGROUND before
blocking the event pump.
