Gardening: Suppress repaint rect differences on XP.
Gardening: Suppress repaint rect differences on XP.

BUG=570581
TBR=pdr@chromium.org
NOTRY=true

Review URL: https://codereview.chromium.org/1530763008

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#365754}

axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk