Disable Failing Viz telemetry_perf_unittests

Update skip list for telemetry_perf_unittests on viz.

Bug: 799594
Change-Id: I18737703c6e98e0275a2fa2b3f99e339529e6c49
Reviewed-on: https://chromium-review.googlesource.com/1101457Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Cr-Commit-Position: refs/heads/master@{#567611}

testing/buildbot/chromium.fyi.json

@@ -1434,7 +1434,9 @@
         "args": [
           "--xvfb",
           "--extra-browser-args=--enable-features=VizDisplayCompositor",
-          "--skip=contrib.cluster_telemetry.screenshot_unittest.ScreenshotUnitTest.testScreenshot"
+          "--skip=contrib.cluster_telemetry.screenshot_unittest.ScreenshotUnitTest.testScreenshot",
+          "--skip=core.perf_benchmark_unittest.PerfBenchmarkTest.testVariationArgs",
+          "--skip=core.perf_benchmark_unittest.PerfBenchmarkTest.testVariationArgsReference"
         ],
         "isolate_name": "telemetry_perf_unittests",
         "name": "telemetry_perf_unittests_viz",

testing/buildbot/test_suites.pyl

@@ -1616,6 +1616,8 @@
         '--xvfb',
         '--extra-browser-args=--enable-features=VizDisplayCompositor',
 	'--skip=contrib.cluster_telemetry.screenshot_unittest.ScreenshotUnitTest.testScreenshot',
+	'--skip=core.perf_benchmark_unittest.PerfBenchmarkTest.testVariationArgs',
+	'--skip=core.perf_benchmark_unittest.PerfBenchmarkTest.testVariationArgsReference',
       ],
       'swarming': {
         'hard_timeout': 960,