[iOS] Disabling test in ExternalURLTabUsageRecorderTestCase

ExternalURLTabUsageRecorderTestCase.testEvictedTabReloadFailure always
fails, simulator and device.

"This site can’t be reached" can't be find (but it shown on the page).

Bug: 852341
Cq-Include-Trybots: luci.chromium.try:ios-simulator-full-configs;master.tryserver.chromium.mac:ios-simulator-cronet
Change-Id: I6ccb5d93ecd470ed3ac5e01400fca1677ebfbfeb
TBR: eugenebut@chromium.org
Reviewed-on: https://chromium-review.googlesource.com/1098923Reviewed-by: Jérôme Lebel <jlebel@chromium.org>
Commit-Queue: Jérôme Lebel <jlebel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#566805}

ios/chrome/browser/metrics/external_url_tab_usage_recorder_egtest.mm

@@ -30,14 +30,10 @@ const char kTestUrl[] =
 @implementation ExternalURLTabUsageRecorderTestCase
 
 // TODO(crbug.com/847948): This test is faling on devices.
-#if TARGET_IPHONE_SIMULATOR
-#define MAYBE_testEvictedTabReloadFailure testEvictedTabReloadFailure
-#else
-#define MAYBE_testEvictedTabReloadFailure DISABLED_testEvictedTabReloadFailure
-#endif
+// TODO(crbug.com/852341): This test is faling on simulators.
 // Verify correct recording of metrics when the reloading of an evicted tab
 // fails.
-- (void)MAYBE_testEvictedTabReloadFailure {
+- (void)DISABLED_testEvictedTabReloadFailure {
   web::test::SetUpFileBasedHttpServer();
   chrome_test_util::HistogramTester histogramTester;
   FailureBlock failureBlock = ^(NSString* error) {