Sheriff: Disable Flaky FilesAppBrowserTests in TabletMode.

Flaky tests include: (FileDisplay|QuickView)/FilesAppBrowserTest.Test/(fileDisplayDrive|openQuickView|fileDisplayDownloads)_TabletMode.

Flake occurrences can be viewed at https://analysis.chromium.org/p/chromium/flake-portal/flakes/occurrences?key=ag9zfmZpbmRpdC1mb3ItbWVyOgsSBUZsYWtlIi9jaHJvbWl1bUBicm93c2VyX3Rlc3RzQEZpbGVzQXBwQnJvd3NlclRlc3QuVGVzdAw

TBR: lucmult@chromium.org
Bug: 1102947
Change-Id: Id39ff39a94e955f0a513b7e5ddceef264846beae
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2285298Reviewed-by: Darwin Huang <huangdarwin@chromium.org>
Commit-Queue: Darwin Huang <huangdarwin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#786050}

chrome/browser/chromeos/file_manager/file_manager_browsertest.cc

@@ -40,6 +40,7 @@ struct TestCase {
     return *this;
   }
 
+  // Note: All TabletMode tests are currently disabled (crbug.com/1102947).
   TestCase& TabletMode() {
     options.tablet_mode = true;
     return *this;
@@ -233,10 +234,12 @@ WRAPPED_INSTANTIATE_TEST_SUITE_P(
     ::testing::Values(
         TestCase("fileDisplayDownloads"),
         TestCase("fileDisplayDownloads").InGuestMode(),
-        TestCase("fileDisplayDownloads").TabletMode(),
+        // Disabled flaky test (crbug.com/1102947)
+        // TestCase("fileDisplayDownloads").TabletMode(),
         TestCase("fileDisplayLaunchOnLocalFolder").DontObserveFileTasks(),
         TestCase("fileDisplayLaunchOnDrive").DontObserveFileTasks(),
-        TestCase("fileDisplayDrive").TabletMode(),
+        // Disabled flaky test (crbug.com/1102947)
+        // TestCase("fileDisplayDrive").TabletMode(),
         TestCase("fileDisplayDrive"),
         TestCase("fileDisplayDriveOffline").Offline(),
         TestCase("fileDisplayDriveOnline"),
@@ -447,7 +450,8 @@ WRAPPED_INSTANTIATE_TEST_SUITE_P(
         TestCase("openQuickViewDialog"),
         TestCase("openQuickViewAndEscape"),
         TestCase("openQuickView").InGuestMode(),
-        TestCase("openQuickView").TabletMode(),
+        // Disabled flaky test (crbug.com/1102947)
+        // TestCase("openQuickView").TabletMode(),
         TestCase("openQuickViewViaContextMenuSingleSelection"),
         TestCase("openQuickViewViaContextMenuCheckSelections"),
         TestCase("openQuickViewAudio"),