Mark a few css-fonts tests as crashing

These are hitting a NOTREACHED() and blocking WPT imports after
https://github.com/w3c/web-platform-tests/pull/9373 landed upstream.

TBR=foolip

Bug: 828748
Change-Id: I72ec5dbe80bd9f5e893a56380acd99aa62a91da0
No-Try: True
Reviewed-on: https://chromium-review.googlesource.com/995094Reviewed-by: Raphael Kubo da Costa <raphael.kubo.da.costa@intel.com>
Commit-Queue: Raphael Kubo da Costa <raphael.kubo.da.costa@intel.com>
Cr-Commit-Position: refs/heads/master@{#548006}

third_party/WebKit/LayoutTests/TestExpectations

@@ -2262,6 +2262,9 @@ crbug.com/626703 [ Debug ] external/wpt/html/semantics/tabular-data/processing-m
 crbug.com/666993 external/wpt/requestidlecallback/callback-idle-periods.html [ Timeout ]
 
 # Crashes with DCHECK enabled, but not on normal Release builds.
+crbug.com/828748 external/wpt/css/css-fonts/variations/font-shorthand.html [ Pass Crash Failure ]
+crbug.com/828748 external/wpt/css/css-fonts/variations/font-style-interpolation.html [ Pass Crash ]
+crbug.com/828748 external/wpt/css/css-fonts/variations/font-weight-lighter-bolder.html [ Pass Crash Failure ]
 crbug.com/626703 external/wpt/css/css-ui/text-overflow-011.html [ Failure Crash Pass ]
 crbug.com/626703 external/wpt/workers/opaque-origin.html [ Failure Crash Timeout ]
 crbug.com/626703 external/wpt/html/rendering/non-replaced-elements/margin-collapsing-quirks/multicol-quirks-mode.html [ Pass Crash ]