Remove trailing whitespace

[zwarich]

The Mach test runner doesn't actually make these failures yet, which is
tracked by #3482.

[hoppipolla-critic-bot]

Critic review: https://critic.hoppipolla.co.uk/r/2782

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[highfive]

Warning

• These commits modify unsafe code. Please review it carefully!

[bors-servo]

saw approval from Manishearth
at https://github.com/zwarich/servo/commit/fb810c08dc4750b271a954d6fdd5af7456741979

[bors-servo]

merging zwarich/servo/trailing-whitespace = fb810c0 into auto

[bors-servo]

zwarich/servo/trailing-whitespace = fb810c0 merged ok, testing candidate = 3dacbfa

[bors-servo]

some tests failed:
failure: http://build.servo.org/builders/linux/builds/156

[bors-servo]

saw approval from Manishearth
at https://github.com/zwarich/servo/commit/fb810c08dc4750b271a954d6fdd5af7456741979

[bors-servo]

saw approval from Manishearth
at https://github.com/zwarich/servo/commit/fb810c08dc4750b271a954d6fdd5af7456741979

[bors-servo]

merging zwarich/servo/trailing-whitespace = fb810c0 into auto

[bors-servo]

zwarich/servo/trailing-whitespace = fb810c0 merged ok, testing candidate = ae946a9

[bors-servo]

all tests pass:
success: http://build.servo.org/builders/linux/builds/167
success: http://build.servo.org/builders/mac/builds/169

[bors-servo]

fast-forwarding master to auto = ae946a9

[gilles-leblanc]

Do we want to remove all trailing white spaces? If so I will remove them as I spot them during other code modifications.

[Manishearth]

Sure, though mach test-tidy should catch most of them