Also disable failing cold startup pages

NOTRY=true

TBR=pasko@chromium.org

Bug: 878175
Change-Id: I759a5d73e4ca9028e05dfba48771971416531680
Reviewed-on: https://chromium-review.googlesource.com/1194251Reviewed-by: Ned Nguyen <nednguyen@google.com>
Commit-Queue: Ned Nguyen <nednguyen@google.com>
Cr-Commit-Position: refs/heads/master@{#586737}

tools/perf/expectations.config

@@ -248,10 +248,11 @@ crbug.com/871708 [ Android_One Android_Webview ] system_health.memory_mobile/bro
 crbug.com/865400 [ Pixel_2 ] system_health.memory_mobile/background:news:nytimes [ Skip ]
 crbug.com/877648 [ Android_Go ] system_health.memory_mobile/long_running:tools:gmail-foreground [ Skip ]
 
-
 # Benchmark: start_with_url.warm.startup_pages
 crbug.com/878175 [ Android ] start_with_url.warm.startup_pages/about:blank [ Skip ]
 crbug.com/878175 [ Android ] start_with_url.warm.startup_pages/http://bbc.co.uk [ Skip ]
+crbug.com/878175 [ Android ] start_with_url.cold.startup_pages/about:blank [ Skip ]
+crbug.com/878175 [ Android ] start_with_url.cold.startup_pages/http://bbc.co.uk [ Skip ]
 
 # Benchmark: tab_switching.typical_25
 crbug.com/747026 [ Mac ] tab_switching.typical_25/multitab:misc:typical24 [ Skip ]