xfvb fails to render with alpha size set

[glennw]

After this commit servo/rust-layers@73d3d71 xfvb appears to be failing to render anything apart from the background on travis + linux.

Is there a GLX error we can detect and fall back if it fails or something like that?

cc @metajack @zwarich @mrobinson

[mrobinson]

How are you testing the build travis with that commit, since as far as I can tell, servo is still using a version of rust-layers a few commits older (c040299)?

[metajack]

@mrobinson the cargoify branch was pointing to the new rust-layers.

[mrobinson]

Ah! I'll take a look. In all likelihood we should simply revert the patch for the moment, but I'll see if I can replicate the failure locally and detect it somehow.

[glennw]

Fixed with the update to rust-layers as part of #3529.