unity8 polling clock continually while display blanked

[Gerry Boland]

With phone screen off, do:

sudo strace -p `pidof unity8`

and observe continual messages like:

poll([{fd=3, events=POLLIN}, {fd=47, events=POLLIN}, {fd=48, events=POLLIN}, {fd=56, events=POLLIN}, {fd=59, events=POLLIN}, {fd=66, events=POLLIN}, {fd=67, events=POLLIN}, {fd=72, events=POLLIN}, {fd=84, events=POLLIN}, {fd=92, events=POLLIN}, {fd=97, events=POLLIN}], 11, 0) = 1 ([{fd=3, revents=POLLIN}])
clock_gettime(CLOCK_MONOTONIC, {1354, 62463620}) = 0
poll([{fd=3, events=POLLIN}, {fd=47, events=POLLIN}, {fd=48, events=POLLIN}, {fd=56, events=POLLIN}, {fd=59, events=POLLIN}, {fd=66, events=POLLIN}, {fd=67, events=POLLIN}, {fd=72, events=POLLIN}, {fd=84, events=POLLIN}, {fd=92, events=POLLIN}, {fd=97, events=POLLIN}], 11, 138) = 1 ([{fd=3, revents=POLLIN}])
read(3, "\1\0\0\0\0\0\0\0", 16) = 8
clock_gettime(CLOCK_MONOTONIC, {1354, 67163758}) = 0
clock_gettime(CLOCK_MONOTONIC, {1354, 68720297}) = 0
poll([{fd=3, events=POLLIN}, {fd=47, events=POLLIN}, {fd=48, events=POLLIN}, {fd=56, events=POLLIN}, {fd=59, events=POLLIN}, {fd=66, events=POLLIN}, {fd=67, events=POLLIN}, {fd=72, events=POLLIN}, {fd=84, events=POLLIN}, {fd=92, events=POLLIN}, {fd=97, events=POLLIN}], 11, 132) = 1 ([{fd=3, revents=POLLIN}])
read(3, "\1\0\0\0\0\0\0\0", 16) = 8
clock_gettime(CLOCK_MONOTONIC, {1354, 75648421}) = 0
clock_gettime(CLOCK_MONOTONIC, {1354, 77449123}) = 0
poll([{fd=3, events=POLLIN}, {fd=47, events=POLLIN}, {fd=48, events=POLLIN}, {fd=56, events=POLLIN}, {fd=59, events=POLLIN}, {fd=66, events=POLLIN}, {fd=67, events=POLLIN}, {fd=72, events=POLLIN}, {fd=84, events=POLLIN}, {fd=92, events=POLLIN}, {fd=97, events=POLLIN}], 11, 123) = 0 (Timeout)

It appears to be continually polling the clock, which is a waste of cycles.