memory.top_10_mobile.reference failing on 2 builders

Regression range: 451009 - 451883

Builders failed on: 
- Android Nexus6 Perf (2): 
  https://build.chromium.org/p/chromium.perf/builders/Android%20Nexus6%20Perf%20%282%29
- Android Nexus7v2 Perf (2): 
  https://build.chromium.org/p/chromium.perf/builders/Android%20Nexus7v2%20Perf%20%282%29

Logs: https://luci-logdog.appspot.com/v/?s=chrome%2Fbb%2Fchromium.perf%2FAndroid_Nexus6_Perf__2_%2F5122%2F%2B%2Frecipes%2Fsteps%2Fmemory.top_10_mobile.reference%2F0%2Fstdout