Make sure the thread is actually paused, and context backep-up, before
SurfaceView is destroyed (eg surfaceDestroyed() actually returns).
Add a timeout when surfaceDestroyed() is called, and check 'backup_done' variable.
It prevents crashes like:
#00 pc 000000000000c0d0 /system/lib64/libutils.so (android::RefBase::incStrong(void const*) const+8)
#01 pc 000000000000c7f4 /vendor/lib64/egl/eglSubDriverAndroid.so (EglAndroidWindowSurface::UpdateBufferList(ANativeWindowBuffer*)+284)
#02 pc 000000000000c390 /vendor/lib64/egl/eglSubDriverAndroid.so (EglAndroidWindowSurface::DequeueBuffer()+240)
#03 pc 000000000000bb10 /vendor/lib64/egl/eglSubDriverAndroid.so (EglAndroidWindowSurface::GetBuffer(EglSubResource*, EglMemoryDesc*)+64)
#04 pc 000000000032732c /vendor/lib64/egl/libGLESv2_adreno.so (EglWindowSurface::UpdateResource(EsxContext*)+116)
#05 pc 0000000000326dd0 /vendor/lib64/egl/libGLESv2_adreno.so (EglWindowSurface::GetResource(EsxContext*, EsxResource**, EsxResource**, int)+56)
#06 pc 00000000002ae484 /vendor/lib64/egl/libGLESv2_adreno.so (EsxContext::AcquireBackBuffer(int)+364)
#07 pc 0000000000249680 /vendor/lib64/egl/libGLESv2_adreno.so (EsxContext::Clear(unsigned int, unsigned int, unsigned int, EsxClearValues*)+1800)
#08 pc 00000000002cb52c /vendor/lib64/egl/libGLESv2_adreno.so (EsxGlApiParamValidate::GlClear(EsxDispatch*, unsigned int)+132)
The internal function SDL_EGL_LoadLibrary() did not delete and remove a mostly
uninitialized data structure if loading the library first failed. A later try to
use EGL then skipped initialization and assumed it was previously successful
because the data structure now already existed. This led to at least one crash
in the internal function SDL_EGL_ChooseConfig() because a NULL pointer was
dereferenced to make a call to eglBindAPI().
