Disable flaky StorageMonitorLinuxTest.DevicePartitionSize

TBR=thestig@chromium.org

Bug: 1010782
Change-Id: Ia8f9070e7b4bf8e5b3dda4b635d17d5ded8d8d44
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1837319Reviewed-by: Yoichi Osato <yoichio@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Yoichi Osato <yoichio@chromium.org>
Auto-Submit: Yoichi Osato <yoichio@chromium.org>
Cr-Commit-Position: refs/heads/master@{#702328}

components/storage_monitor/storage_monitor_linux_unittest.cc

@@ -660,7 +660,7 @@ TEST_F(StorageMonitorLinuxTest, DeviceLookUp) {
   EXPECT_EQ(1, observer().detach_calls());
 }
 
-TEST_F(StorageMonitorLinuxTest, DevicePartitionSize) {
+TEST_F(StorageMonitorLinuxTest, DISABLED_DevicePartitionSize) {
   base::FilePath test_path_a = CreateMountPointWithDCIMDir(kMountPointA);
   base::FilePath test_path_b = CreateMountPointWithoutDCIMDir(kMountPointB);
   ASSERT_FALSE(test_path_a.empty());