Auto merge of #1025 - servo:kvark-patch-2, r=glennw
Auto merge of #1025 - servo:kvark-patch-2, r=glennw

Fix the `max_texture_size` checks

The size of `max_texture_size` should still be allowed, and that's what the rest of the code assumes.
potentially fixes https://treeherder.mozilla.org/logviewer.html#?job_id=87300231&repo=try&lineNumber=3307
cc @staktrace
r? @glennw

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