[ChromeDriver] Disabling test MobileEmulationCapabilityTest.testDeviceMetricsWithDeviceWidth

Test testDeviceMetricsWithDeviceWidth occasionally fails in Chromedriver test automation on Linux build bot.

Bug: chromedriver:2132
Change-Id: If38097aee1ada7c7e7b7e7832e9643279a14011c
Reviewed-on: https://chromium-review.googlesource.com/769156
Reviewed-by: John Chen <johnchen@chromium.org>
Commit-Queue: Artur Khachatryan <khachatryan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#516377}