[Sheriff] Disable a couple of LayoutTests on Mac.

There were failing.
* css1/font_properties/font.html
* css1/font_properties/font_family.html
* css2.1/t1503-c522-font-family-00-b.html
* css2.1/t1508-c527-font-03-b.html
* fast/block/float/016.html
* fast/text/international/complex-character-based-fallback.html
* fonts/cursive.html
* svg/text/ligature-queries.html

Tbr: drott@chromium.org
Bug: 910263
Change-Id: If5a9291579bff7d8c3184a8c02813088df6c06f5
Reviewed-on: https://chromium-review.googlesource.com/c/1355523Reviewed-by: Sebastien Seguin-Gagnon <sebsg@chromium.org>
Commit-Queue: Sebastien Seguin-Gagnon <sebsg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#612346}

third_party/blink/web_tests/TestExpectations

@@ -5754,3 +5754,11 @@ crbug.com/908347 [ Mac ] media/autoplay/webaudio-audio-context-resume.html [ Fai
 
 # Sheriff 2018-11-29
 crbug.com/905772 [ Linux ] inspector-protocol/memory/sampling-native-profile-blink-gc.js [ Failure Pass ]
+crbug.com/910263 [ Mac ] css1/font_properties/font.html [ Pass Crash Failure ]
+crbug.com/910263 [ Mac ] css1/font_properties/font_family.html [ Pass Crash Failure ]
+crbug.com/910263 [ Mac ] css2.1/t1503-c522-font-family-00-b.html [ Pass Crash Failure ]
+crbug.com/910263 [ Mac ] css2.1/t1508-c527-font-03-b.html [ Pass Crash Failure ]
+crbug.com/910263 [ Mac ] fast/block/float/016.html [ Pass Crash Failure ]
+crbug.com/910263 [ Mac ] fast/text/international/complex-character-based-fallback.html [ Pass Crash Failure ]
+crbug.com/910263 [ Mac ] fonts/cursive.html [ Pass Crash Failure ]
+crbug.com/910263 [ Mac ] svg/text/ligature-queries.html [ Pass Crash Failure ]