Disable flaky SecurityInterstitialTabHelperTest.MultipleBlockingPages

TBR=carlosil@chromium.org

Bug: 1010183
Change-Id: Ic57588d5ab510b780955552f5393e6cb94ab75f2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1837438Reviewed-by: Yoichi Osato <yoichio@chromium.org>
Commit-Queue: Yoichi Osato <yoichio@chromium.org>
Auto-Submit: Yoichi Osato <yoichio@chromium.org>
Cr-Commit-Position: refs/heads/master@{#702321}

components/security_interstitials/content/security_interstitial_tab_helper_unittest.cc

@@ -129,7 +129,7 @@ TEST_F(SecurityInterstitialTabHelperTest, SingleBlockingPage) {
 
 // Tests that the helper properly handles the lifetime of multiple blocking
 // pages, committed in a different order than they are created.
-TEST_F(SecurityInterstitialTabHelperTest, MultipleBlockingPages) {
+TEST_F(SecurityInterstitialTabHelperTest, DISABLED_MultipleBlockingPages) {
   // Simulate associating the first interstitial.
   std::unique_ptr<content::NavigationHandle> handle1 =
       CreateHandle(true, false);