ignore flaky failure on android

this failed to commit the first time

NOTREECHECKS=true
NOTRY=true
R=bsalomon@google.com
TBR=bsalomon

Author: caryclark@google.com

Review URL: https://codereview.chromium.org/488273002
diff --git a/expectations/gm/Test-Android-Reference-Unknown-Arm64-Release/expected-results.json b/expectations/gm/Test-Android-Reference-Unknown-Arm64-Release/expected-results.json
index 4973edd..09f82c4 100644
--- a/expectations/gm/Test-Android-Reference-Unknown-Arm64-Release/expected-results.json
+++ b/expectations/gm/Test-Android-Reference-Unknown-Arm64-Release/expected-results.json
@@ -8494,6 +8494,7 @@
           5520583909201375586
         ]
       ], 
+      "ignore-failure": true,
       "reviewed-by-human": true
     }, 
     "patch_primitive_565.png": {