disable OptimizationGuidePredictionsNotAppliedForAlreadyCommittedNavigation

Flakiness on https://ci.chromium.org/p/chromium/builders/ci/Network%20Service%20Linux

Sample output:
 [ RUN      ] LoadingPredictorBrowserTestWithOptimizationGuide.OptimizationGuidePredictionsNotAppliedForAlreadyCommittedNavigation/1
 [22182:22182:0330/211059.950234:15709478620:ERROR:edid_parser.cc(102)] Too short EDID data: manufacturer id
 [22182:22182:0330/211100.151354:INFO:content_main_runner_impl.cc(974)] Chrome is running in full browser mode.
 [22182:22462:0330/211100.642123:ERROR:object_proxy.cc(632)] Failed to call method: org.freedesktop.DBus.Properties.Get: object_path= /org/freedesktop/UPower: org.freedesktop.DBus.Error.ServiceUnknown: The name org.freedesktop.UPower was not provided by any .service files
 [22182:22462:0330/211100.642156:WARNING:property.cc(144)] DaemonVersion: GetAndBlock: failed.
 [22182:22462:0330/211100.642407:ERROR:object_proxy.cc(632)] Failed to call method: org.freedesktop.UPower.GetDisplayDevice: object_path= /org/freedesktop/UPower: org.freedesktop.DBus.Error.ServiceUnknown: The name org.freedesktop.UPower was not provided by any .service files
 [22182:22462:0330/211100.642629:ERROR:object_proxy.cc(632)] Failed to call method: org.freedesktop.UPower.EnumerateDevices: object_path= /org/freedesktop/UPower: org.freedesktop.DBus.Error.ServiceUnknown: The name org.freedesktop.UPower was not provided by any .service files
 [22384:22480:0330/211100.706731:WARNING:simple_synchronous_entry.cc(1389)] Could not open platform files for entry.
 [22182:22182:0330/211100.741071:WARNING:gaia_auth_fetcher.cc(989)] Could not reach Google Accounts servers: errno -11
 ../../base/test/metrics/histogram_tester.cc:201: Failure
 Expected equality of these values:
   expected_count
     Which is: 1
   actual_count
     Which is: 0
 Histogram LoadingPredictor.OptimizationHintsReceiveStatus does not have the right number of samples (1) in the expected bucket (2). It has (0).

BUG=chromium:1060966
TBR=tbansal@chromium.org

Change-Id: Ia2ab0b7bc030b6ee68c440e2bfb540ddb8dce95a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2128040Reviewed-by: Johann Koenig <johannkoenig@google.com>
Reviewed-by: Tarun Bansal <tbansal@chromium.org>
Commit-Queue: Johann Koenig <johannkoenig@google.com>
Cr-Commit-Position: refs/heads/master@{#754817}

chrome/browser/predictors/loading_predictor_browsertest.cc

@@ -1651,7 +1651,7 @@ IN_PROC_BROWSER_TEST_P(
   }
 }
 
-// crbug.com/1060966
+// TODO(crbug.com/1060966): Tests are flakey.
 IN_PROC_BROWSER_TEST_P(
     LoadingPredictorBrowserTestWithOptimizationGuide,
     DISABLED_NavigationWithBothLocalPredictionAndOptimizationHint) {
@@ -1816,10 +1816,10 @@ IN_PROC_BROWSER_TEST_P(
   }
 }
 
+// TODO(crbug.com/1060966): Tests are flakey.
 IN_PROC_BROWSER_TEST_P(
     LoadingPredictorBrowserTestWithOptimizationGuide,
-    DISABLE_ON_WIN_MAC_CHROMEOS(
-        OptimizationGuidePredictionsNotAppliedForAlreadyCommittedNavigation)) {
+    DISABLED_OptimizationGuidePredictionsNotAppliedForAlreadyCommittedNavigation) {
   base::HistogramTester histogram_tester;
 
   GURL url = embedded_test_server()->GetURL("hints.com", "/simple.html");