Disable PageLoadMetricsBrowserTest.FirstMeaningfulPaintRecorded on Linux MSan builds

TBR=csharrison@chromium.org

Bug: 1009885
Change-Id: Iddfb99a599c5337b650a6766935e79bbb9580f70
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1833011Reviewed-by: Tsuyoshi Horo <horo@chromium.org>
Commit-Queue: Tsuyoshi Horo <horo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#701474}

chrome/browser/page_load_metrics/page_load_metrics_browsertest.cc

@@ -958,8 +958,14 @@ IN_PROC_BROWSER_TEST_F(PageLoadMetricsBrowserTest,
                   .empty());
 }
 
+// TODO(crbug.com/1009885): Flaky on Linux MSan builds.
+#if defined(MEMORY_SANITIZER) && defined(OS_LINUX)
+#define MAYBE_FirstMeaningfulPaintRecorded DISABLED_FirstMeaningfulPaintRecorded
+#else
+#define MAYBE_FirstMeaningfulPaintRecorded FirstMeaningfulPaintRecorded
+#endif
 IN_PROC_BROWSER_TEST_F(PageLoadMetricsBrowserTest,
-                       FirstMeaningfulPaintRecorded) {
+                       MAYBE_FirstMeaningfulPaintRecorded) {
   ASSERT_TRUE(embedded_test_server()->Start());
 
   auto waiter = CreatePageLoadMetricsTestWaiter();