Disable flakey test: testMultipleCrashMinidumps.

Disables another test for all platforms.

TBR=brucedawson@chromium.org

Bug: 1084931
Change-Id: Id84a3030a4ffa49784c39eb5dfd01c8b92058d6e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2313980Reviewed-by: James MacLean <wjmaclean@chromium.org>
Commit-Queue: James MacLean <wjmaclean@chromium.org>
Cr-Commit-Position: refs/heads/master@{#791017}

tools/perf/core/minidump_unittest.py

@@ -78,12 +78,8 @@ class BrowserMinidumpTest(tab_test_case.TabTestCase):
   # Minidump symbolization doesn't work in ChromeOS local mode if the rootfs is
   # still read-only, so skip the test in that case.
   # TODO(crbug.com/1038043): Test is failing on chromeos-betty-chrome.
-  @decorators.Disabled(
-      'chromeos-local',
-      'chromeos-board-betty',
-      'chromeos-board-betty-pi-arc',
-      'win'  # https://crbug.com/1084931
-  )
+  # TODO(crbug.com/1084931): Test is failing on win, mac, others?
+  @decorators.Disabled('all')
   def testMultipleCrashMinidumps(self):
     # Wait for the browser to restart fully before crashing
     self._LoadPageThenWait('var cat = "dog";', 'cat')