Deflake fast/css/no-recalc-on-no-op-inline-style-changes.html

The test had an assumption about a style recalc count at a point during
loading which was not preceeded by a forced recalc at any point. The
result was undefined and it did not test anything useful. Add a forced
recalc through offsetTop before the test instead.

Bug: 904587
Change-Id: I17d00e017a625ca10f71ebfd3a946266d6ea9ff5
Reviewed-on: https://chromium-review.googlesource.com/c/1332431Reviewed-by: Morten Stenshorne <mstensho@chromium.org>
Commit-Queue: Rune Lillesveen <futhark@chromium.org>
Cr-Commit-Position: refs/heads/master@{#607536}

third_party/WebKit/LayoutTests/TestExpectations

@@ -4551,9 +4551,6 @@ crbug.com/778745 http/tests/inspector-protocol/cachestorage/read-cached-response
 # Sheriff failures 2017-10-24
 crbug.com/773122 crbug.com/777813 [ Win ] fast/text/font-ascent-mac.html [ Failure Pass ]
 
-# Sheriff failures 2017-11-07
-crbug.com/782067 [ Mac10.10 Mac10.11 ] fast/css/no-recalc-on-no-op-inline-style-changes.html [ Pass Failure ]
-
 # Sheriff failures 2017-11-13
 crbug.com/783800 external/wpt/imagecapture/MediaStreamTrack-applyConstraints.html [ Pass Failure ]
 crbug.com/783800 external/wpt/imagecapture/MediaStreamTrack-applyConstraints-getSettings.html [ Pass Failure ]

third_party/WebKit/LayoutTests/fast/css/no-recalc-on-no-op-inline-style-changes.html

@@ -8,8 +8,7 @@ test(function () {
   if (!window.internals)
     assert_unreached('This test requires window.internals.');
 
-  assert_greater_than(internals.updateStyleAndReturnAffectedElementCount(), 1);
-
+  element.offsetTop;
   element.style.top = "0px";
   assert_equals(internals.updateStyleAndReturnAffectedElementCount(), 1);