Disable flaky PageLoadMetricsBrowserTests on Linux

chrome/browser/page_load_metrics/page_load_metrics_browsertest.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/files/scoped_temp_dir.h"
 #include "base/macros.h"
 #include "base/test/histogram_tester.h"
 #include "base/time/time.h"
 #include "chrome/browser/page_load_metrics/metrics_web_contents_observer.h"
 #include "chrome/browser/page_load_metrics/observers/aborts_page_load_metrics_observer.h"
@@ skipping 497 matching lines @@
 
   histogram_tester_.ExpectUniqueSample(
       internal::kHistogramFirstMeaningfulPaintStatus,
       internal::FIRST_MEANINGFUL_PAINT_DID_NOT_REACH_NETWORK_STABLE, 1);
   histogram_tester_.ExpectTotalCount(
       internal::kHistogramFirstMeaningfulPaint, 0);
   histogram_tester_.ExpectTotalCount(
       internal::kHistogramParseStartToFirstMeaningfulPaint, 0);
 }
 
+// Flaky on Linux (timing out or failing in an expectation) crbug.com/657022
+#if defined(OS_LINUX)
+#define MAYBE_NoStatePrefetchObserverCacheable \
+  DISABLED_NoStatePrefetchObserverCacheable
+#else
+#define MAYBE_NoStatePrefetchObserverCacheable NoStatePrefetchObserverCacheable
+#endif
 IN_PROC_BROWSER_TEST_F(PageLoadMetricsBrowserTest,
-                       NoStatePrefetchObserverCacheable) {
+                       MAYBE_NoStatePrefetchObserverCacheable) {
   ASSERT_TRUE(embedded_test_server()->Start());
 
   ui_test_utils::NavigateToURL(browser(),
                                embedded_test_server()->GetURL("/title1.html"));
   NavigateToUntrackedUrl();
 
   histogram_tester_.ExpectTotalCount(
       "Prerender.none_PrefetchTTFCP.Reference.NoStore.Visible", 0);
   histogram_tester_.ExpectTotalCount(
       "Prerender.none_PrefetchTTFCP.Reference.Cacheable.Visible", 1);
 }
 
+// Flaky on Linux (timing out or failing in an expectation) crbug.com/657022
+#if defined(OS_LINUX)
+#define MAYBE_NoStatePrefetchObserverNoStore \
+  DISABLED_NoStatePrefetchObserverNoStore
+#else
+#define MAYBE_NoStatePrefetchObserverNoStore NoStatePrefetchObserverNoStore
+#endif
 IN_PROC_BROWSER_TEST_F(PageLoadMetricsBrowserTest,
-                       NoStatePrefetchObserverNoStore) {
+                       MAYBE_NoStatePrefetchObserverNoStore) {
   ASSERT_TRUE(embedded_test_server()->Start());
 
   ui_test_utils::NavigateToURL(browser(),
                                embedded_test_server()->GetURL("/nostore.html"));
   NavigateToUntrackedUrl();
 
   histogram_tester_.ExpectTotalCount(
       "Prerender.none_PrefetchTTFCP.Reference.NoStore.Visible", 1);
   histogram_tester_.ExpectTotalCount(
       "Prerender.none_PrefetchTTFCP.Reference.Cacheable.Visible", 0);
@@ skipping 26 matching lines @@
   ui_test_utils::NavigateToURL(browser(), embedded_test_server()->GetURL(
                                               "/page_load_metrics/large.html"));
   NavigateToUntrackedUrl();
 
   histogram_tester_.ExpectTotalCount(internal::kHistogramTotalBytes, 1);
 
   // Verify that there is a single sample recorded in the 10kB bucket (the size
   // of the main HTML response).
   histogram_tester_.ExpectBucketCount(internal::kHistogramTotalBytes, 10, 1);
 }