Look for the NINJA_PATH env var and prefer that over the bootstrapped ninja

The snapshot ninja may cause issues in some environments, where a different
ninja version may work. If the user has NINJA_PATH set in their environment,
prefer that over bootstrapping our own.

Change-Id: I4c6d2f479aeae1f5137705ed2deb995b59ea287a
Reviewed-by: Andras Becsi <andras.becsi@digia.com>
Disable geolocation

This prevents the crash when a webpage requests geolocation permission.

Change-Id: I7331b869ec1439d678cee7941691289220718f3d
Reviewed-by: Zeno Albisser <zeno.albisser@digia.com>