Disable rendering.desktop/css_value_type_shadow on win7.

This is failing consistently.

BUG=1059723
NOTRY=true
CC=sadrul@chromium.org,vmiura@chromium.org
TBR=crouleau@chromium.org

Change-Id: I0d574137067b2a199f6c4543055a2a29db6c24b4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2093476Reviewed-by: Stephen Nusko <nuskos@chromium.org>
Commit-Queue: Stephen Nusko <nuskos@chromium.org>
Auto-Submit: Stephen Nusko <nuskos@chromium.org>
Cr-Commit-Position: refs/heads/master@{#748173}

tools/perf/expectations.config

@@ -224,6 +224,7 @@ crbug.com/1044962 [ win ] rendering.desktop/camera_to_webgl [ Skip ]
 crbug.com/1053614 [ win ] rendering.desktop/filter_terrain_svg [ Skip ]
 crbug.com/1059200 [ win7 ] rendering.desktop/canvas_to_blob [ Skip ]
 crbug.com/1059273 [ win7 ] rendering.desktop/css_transitions_inline_style [ Skip ]
+crbug.com/1059723 [ win7 ] rendering.desktop/css_value_type_shadow [ Skip ]
 
 # Benchmark: rendering.mobile
 crbug.com/785485 [ android-webview ] rendering.mobile/kevs_3d [ Skip ]