iris: fix some hangs around null framebuffers
This fixes some cases in fbo-none* and framebuffer_no_attachments.
I'm not sure this is correct otherwise, the tests don't all pass yet
No idea if this is in any way the correct answer
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This fixes some cases in fbo-none* and framebuffer_no_attachments.
I'm not sure this is correct otherwise, the tests don't all pass yet
No idea if this is in any way the correct answer