Disable flaky Metric..LargestContentfulPaint..

MetricIntegrationTest.LargestContentfulPaint_SubframeInput is flaky on
Linux, so disabling there (and for Chrome OS as well).

TBR=skobes

Bug: 1135527
Change-Id: I876e3e1d174edca0b5bd17f3cc53f3cb61ef4c19
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2467522Reviewed-by: Thiemo Nagel <tnagel@chromium.org>
Commit-Queue: Thiemo Nagel <tnagel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#816521}

chrome/browser/page_load_metrics/integration_tests/largest_contentful_paint_browsertest.cc

@@ -133,7 +133,7 @@ IN_PROC_BROWSER_TEST_F(MetricIntegrationTest, LargestContentfulPaint) {
 }
 
 // Flaky on Win7, see crbug.com/1135527
-#if defined(OS_WIN)
+#if defined(OS_WIN) || defined(OS_LINUX) || defined(OS_CHROMEOS)
 #define MAYBE_LargestContentfulPaint_SubframeInput \
   DISABLED_LargestContentfulPaint_SubframeInput
 #else