servo: Merge #16237 - Fix Android issues: update servo-glutin & offsc…

…reen_gl_context (from MortimerGoro:update_glutin_offscreen); r=jdm

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See servo/surfman#94 and servo/glutin#121

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Source-Repo: https://github.com/servo/servo
Source-Revision: f659d43bd403e4ac1305990ba704f23b4a6cd5e6

--HG--
extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear
extra : subtree_revision : 76e38ca77cc9227bfaa6f30cc6445cdfcbacf29c