[Sheriff] Disable two flaky tests in AdsPageLoadMetricsObserverBrowserTest

TBR=kinuko@chromium.org

Bug: 1113696, 1113692
Change-Id: I2e949d45670d0155dc45c125904d35386ecbd38e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2340184
Commit-Queue: Fabio Tirelo <ftirelo@chromium.org>
Reviewed-by: Fabio Tirelo <ftirelo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#795539}

chrome/browser/page_load_metrics/observers/ad_metrics/ads_page_load_metrics_observer_browsertest.cc

@@ -250,8 +250,14 @@ IN_PROC_BROWSER_TEST_F(AdsPageLoadMetricsObserverBrowserTest,
 // a page's lifecycling by creating a large ad frame, destroying it, and
 // creating a smaller iframe. The ad density recorded is the density with
 // the first larger frame.
+#if defined(OS_CHROMEOS)
+// TODO(http://crbug.com/1113692): flaky on ChromeOS.
+#define MAYBE_PageAdDensityRecordsPageMax DISABLED_PageAdDensityRecordsPageMax
+#else
+#define MAYBE_PageAdDensityRecordsPageMax PageAdDensityRecordsPageMax
+#endif
 IN_PROC_BROWSER_TEST_F(AdsPageLoadMetricsObserverBrowserTest,
-                       PageAdDensityRecordsPageMax) {
+                       MAYBE_PageAdDensityRecordsPageMax) {
   base::HistogramTester histogram_tester;
   ukm::TestAutoSetUkmRecorder ukm_recorder;
   auto waiter = CreatePageLoadMetricsTestWaiter();
@@ -424,8 +430,16 @@ IN_PROC_BROWSER_TEST_F(AdsPageLoadMetricsObserverBrowserTest,
 
 // Creates a frame with display:none styling and verifies that it has an
 // empty intersection with the main frame.
+#if defined(OS_CHROMEOS)
+// TODO(http://crbug.com/1113696): flaky on ChromeOS.
+#define MAYBE_PageAdDensityIgnoreDisplayNoneFrame \
+  DISABLED_PageAdDensityIgnoreDisplayNoneFrame
+#else
+#define MAYBE_PageAdDensityIgnoreDisplayNoneFrame \
+  PageAdDensityIgnoreDisplayNoneFrame
+#endif
 IN_PROC_BROWSER_TEST_F(AdsPageLoadMetricsObserverBrowserTest,
-                       PageAdDensityIgnoreDisplayNoneFrame) {
+                       MAYBE_PageAdDensityIgnoreDisplayNoneFrame) {
   base::HistogramTester histogram_tester;
   ukm::TestAutoSetUkmRecorder ukm_recorder;
   auto waiter = CreatePageLoadMetricsTestWaiter();