Broken on Chromebook

[steren]

[.WebGL-0x318401b02300]GL ERROR :GL_INVALID_FRAMEBUFFER_OPERATION : glDrawArrays: framebuffer incomplete (check)

[steren]

Probably need to merge evanw/webgl-path-tracing#2

[steren]

Most likely fixed in steren/webgl-path-tracing@ddccbca