Move static methods to the end of DrmEngine
Move static methods to the end of DrmEngine

Moved all the static methods in DrmEngine to the bottom of
the class (general practice).

Change-Id: Iec8f747e61db931d8fc09838ce32ec1852f0fced

shaka-project/shaka-player,tvoli/shaka-player,shaka-project/shaka-player,tvoli/shaka-player,tvoli/shaka-player,shaka-project/shaka-player,shaka-project/shaka-player,tvoli/shaka-player