vcl: Fix pixel drawing with OpenGL

Change-Id: I5d8e80baec9537e0c5913d821e26566409fe5261
vcl: Add methods to call before and after OpenGL rendering

Change-Id: I937907a3e8eb8f841a2eed6199e86d022be7dc16
vcl: Remove unused shaders list

Change-Id: I13a25a39cceb184c2bb2b48bc143a951ee982b26
vcl: Use a different FBO when rendering using a VirtualDevice

Change-Id: I8cb97a4057c06ca09adfcac8dcd3f61ac9508430