Compute value of float according to position value
According to CSS2 Section 9.7, if 'position' has a value of 'absolute'
or 'fixed' the computed value of 'float' should be 'none'.
This changes the float to a single_keyword_computed which checks the
positioned value of the element to compute the float value.
Fixes#8002
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Add destructors to some WebGL objects, remove duplicated glutin dependency and try to enable the webgl reftests
The first commit allows to cleanup the gl resources of the webgl task earlier if they aren't being used.
Right now all resources were cleaned up when the context was destroyed, so I think this is
a slightly better approach.
The second commit bumps rust-offscreen-rendering-context to remove the duplicated glutin dependency.
The third one tries to reenable the webgl reftests.
Since the errored builds are deleted, It's the only way I can try to troubleshoot it.
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Before passing these layers to the paint task, expand them to pixel
boundaries. This ensures that subpixel edges of the layer will not be
clipped away and helps prevent rounding issues with layer contents.
Fixes#8166.
Made block type pattern match less inclusive
Given the comments above the match statement, it seems that fixed-pos check should match only block elements in this case. Doing this change seems to partially resolve the issue where list items with `position:fixed;` styling are not displaying their bullet points. This change only resolves the issue for list items with `list-style-position: inside`, outside positioning is still not functioning correctly.
https://github.com/servo/servo/issues/8001#issuecomment-149781613
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According to CSS2 Section 9.7, if 'position' has a value of 'absolute'
or 'fixed' the computed value of 'float' should be 'none'.
This changes the float to a single_keyword_computed which checks the
positioned value of the element to compute the float value.
Fixes#8002
