Disable flaky test

ResolutionNotificationControllerTest.MultipleResolutionChange.

TBR=tetsui@chromium.org,yoshiki@chromium.org,estade@chromium.org

Bug: 869401
Change-Id: Ic2cd931481cc43ac900c829f8f6b82a4e632ce63
Reviewed-on: https://chromium-review.googlesource.com/1156850Reviewed-by: Roger Tawa <rogerta@chromium.org>
Commit-Queue: Roger Tawa <rogerta@chromium.org>
Cr-Commit-Position: refs/heads/master@{#579449}

ash/display/resolution_notification_controller_unittest.cc

@@ -319,7 +319,9 @@ TEST_F(ResolutionNotificationControllerTest, DisplayDisconnected) {
   EXPECT_EQ(59.0f, mode.refresh_rate());
 }
 
-TEST_F(ResolutionNotificationControllerTest, MultipleResolutionChange) {
+// See http://crbug.com/869401 for details.
+TEST_F(ResolutionNotificationControllerTest,
+       DISABLED_MultipleResolutionChange) {
   UpdateDisplay(
       "300x300#300x300%56|200x200%57,"
       "250x250#250x250%58|200x200%59");