Skip Telemetry minidump tests on local CrOS

Stack symbolization is known to not work on CrOS if the test is being
run locally (as opposed to over SSH) and the root filesystem is set to
read-only. So, skip the Telemetry minidump stack symbolization tests
on CrOS if we detect that we're running in local mode.

Bug: 1014177
Change-Id: If2ca8f43b0aa76db47d5feb447501b8fe8f3be6e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1860760Reviewed-by: Caleb Rouleau <crouleau@chromium.org>
Commit-Queue: Brian Sheedy <bsheedy@chromium.org>
Auto-Submit: Brian Sheedy <bsheedy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#707506}

tools/perf/core/minidump_unittest.py

@@ -19,7 +19,9 @@ class BrowserMinidumpTest(tab_test_case.TabTestCase):
   @decorators.Isolated
   # Android is currently hard coded to return None for minidump paths.
   # Flakes on chromeos: crbug.com/1014754
-  @decorators.Disabled('android', 'chromeos')
+  # Minidump symbolization doesn't work in ChromeOS local mode if the rootfs is
+  # still read-only, so skip the test in that case.
+  @decorators.Disabled('android', 'chromeos', 'chromeos-local')
   def testSymbolizeMinidump(self):
     # Wait for the browser to restart fully before crashing
     self._LoadPageThenWait('var sam = "car";', 'sam')
@@ -93,7 +95,9 @@ class BrowserMinidumpTest(tab_test_case.TabTestCase):
 
   @decorators.Isolated
   # Flakes on chromeos: crbug.com/1014754
-  @decorators.Disabled('android', 'chromeos')
+  # Minidump symbolization doesn't work in ChromeOS local mode if the rootfs is
+  # still read-only, so skip the test in that case.
+  @decorators.Disabled('android', 'chromeos', 'chromeos-local')
   def testMultipleCrashMinidumps(self):
     # Wait for the browser to restart fully before crashing
     self._LoadPageThenWait('var cat = "dog";', 'cat')

tools/perf/expectations.config

 # Test Expectation file for telemetry tests.
 # Instructions of how to use this file:
 # https://chromium.googlesource.com/chromium/src/+/master/docs/speed/bot_health_sheriffing/how_to_disable_a_story.md
-# tags: [ android chromeos linux mac mac-10.11 mac-10.12 win win10 win7 sierra highsierra
+# tags: [ android chromeos chromeos-local chromeos-remote linux mac mac-10.11 mac-10.12 win win10 win7 sierra highsierra
 #         android-marshmallow android-lollipop android-nougat android-oreo android-pie android-10
 #         android-kitkat ubuntu ]
 # tags: [ android-go android-low-end android-nexus-5 android-nexus-5x android-nexus-6