Add android_optional_gpu_tests_rel to master.tryserver.chromium.android.

masters/master.tryserver.chromium.android/builders.pyl

Index: masters/master.tryserver.chromium.android/builders.pyl
diff --git a/masters/master.tryserver.chromium.android/builders.pyl b/masters/master.tryserver.chromium.android/builders.pyl
index 99615e1819af4f69af358bc627d1e1cbd233e5b0..0e10f7558123e0ee9e1980a9d4e34de45bdb7535 100644
--- a/masters/master.tryserver.chromium.android/builders.pyl
+++ b/masters/master.tryserver.chromium.android/builders.pyl
@@ -170,6 +170,13 @@
       "slavebuilddir": "android_chromium_variable_archive",
       "slave_pools": ["ccompute_optional_bots"],
     },
+    "android_optional_gpu_tests_rel": {
+      "builder_timeout_s": 6900,  # 60 * 115
+      "recipe": "chromium_trybot",
+      "scheduler": None,
+      "slavebuilddir": "android",
+      "slave_pools": ["ccompute_android_launch"],
+    },
   },
 
   "schedulers": { },