I'm enabling snapshot_unittests on all bots in https://chromium-review.googlesource.com/c/chromium/src/+/1089655

It fails on win10:
https://ci.chromium.org/p/chromium/builders/luci.chromium.try/win10_chromium_x64_rel_ng/23370

SnapshotAuraTest.RotateAndUIScaleAndScaleFactor
SnapshotAuraTest.PartialBounds
SnapshotAuraTest.DeviceScaleFactor
SnapshotAuraTest.Rotated
SnapshotAuraTest.UIScale
SnapshotAuraTest.RotateAndUIScale
SnapshotAuraTest.FullScreenWindow


Stacks all look like some kind of

[ RUN      ] SnapshotAuraTest.Rotated
../../ui/snapshot/snapshot_aura_unittest.cc(215): error: Expected equality of these values:
  test_bounds.size().ToString()
    Which is: "300x200"
  snapshot.Size().ToString()
    Which is: "200x300"
Stack trace:
Backtrace:
	testing::internal::UnitTestImpl::CurrentOsStackTraceExceptTop [0x00007FF66CC90243+87]
	testing::internal::AssertHelper::operator= [0x00007FF66CC8FDE8+78]
	ui::SnapshotAuraTest_Rotated_Test::TestBody [0x00007FF66C991854+328]
../../ui/snapshot/snapshot_aura_unittest.cc(216): error: Expected equality of these values:
  0u
    Which is: 0
  GetFailedPixelsCount(snapshot)
    Which is: 60000
Stack trace:
Backtrace:
	testing::internal::UnitTestImpl::CurrentOsStackTraceExceptTop [0x00007FF66CC90243+87]
	testing::internal::AssertHelper::operator= [0x00007FF66CC8FDE8+78]
	ui::SnapshotAuraTest_Rotated_Test::TestBody [0x00007FF66C99191B+527]



(The test passes fine on win7: https://ci.chromium.org/p/chromium/builders/luci.chromium.try/win7_chromium_rel_ng/8742)