Enable GLContextHelper and register a SurfaceFactoryQt on eAndroid

This is needed to run on certain hardware that needs the shared EGL
contexts to be created on the same thread.
To prevent a deadlock on eAndroid only use a blocking connection
if we are not on the main thread where the singleton was created,
since there is a call to this from gpu_info_collector_android
before the GPU thread is launched.

Change-Id: I6887ad1218b8426097f454741dc5a79ee94f9d62
Reviewed-by: Jocelyn Turcotte <jocelyn.turcotte@digia.com>