diff --git a/.buildkite/pipeline.yml b/.buildkite/pipeline.yml
index 515f0e98c..6c5870db8 100644
--- a/.buildkite/pipeline.yml
+++ b/.buildkite/pipeline.yml
@@ -238,17 +238,23 @@
       --test_env=RAY_USE_MULTIPROCESSING_CPU_COUNT=1
       rllib/...
 
-- label: ":brain: RLlib: rllib/examples/ {1/2}"
+- label: ":brain: RLlib: Examples {A/B}"
   conditions: ["RAY_CI_RLLIB_AFFECTED"]
   commands:
     - cleanup() { if [ "${BUILDKITE_PULL_REQUEST}" = "false" ]; then ./ci/travis/upload_build_info.sh; fi }; trap cleanup EXIT
     - RLLIB_TESTING=1 ./ci/travis/install-dependencies.sh
     - bazel test --config=ci $(./scripts/bazel_export_options) --build_tests_only
       --test_tag_filters=examples_A,examples_B,-flaky --test_env=RAY_USE_MULTIPROCESSING_CPU_COUNT=1 rllib/...
+
+- label: ":brain: RLlib: Examples {C/D}"
+  conditions: ["RAY_CI_RLLIB_AFFECTED"]
+  commands:
+    - cleanup() { if [ "${BUILDKITE_PULL_REQUEST}" = "false" ]; then ./ci/travis/upload_build_info.sh; fi }; trap cleanup EXIT
+    - RLLIB_TESTING=1 ./ci/travis/install-dependencies.sh
     - bazel test --config=ci $(./scripts/bazel_export_options) --build_tests_only
       --test_tag_filters=examples_C,examples_D,-flaky --test_env=RAY_USE_MULTIPROCESSING_CPU_COUNT=1 rllib/...
 
-- label: ":brain: RLlib: rllib/examples/ {2/2}"
+- label: ":brain: RLlib: Examples {E/P}"
   conditions: ["RAY_CI_RLLIB_AFFECTED"]
   commands:
     - cleanup() { if [ "${BUILDKITE_PULL_REQUEST}" = "false" ]; then ./ci/travis/upload_build_info.sh; fi }; trap cleanup EXIT
@@ -256,10 +262,17 @@
     - bazel test --config=ci $(./scripts/bazel_export_options) --build_tests_only
       --test_tag_filters=examples_E,examples_F,examples_G,examples_H,examples_I,examples_J,examples_K,examples_L,examples_M,examples_N,examples_O,examples_P,-flaky --test_env=RAY_USE_MULTIPROCESSING_CPU_COUNT=1
       rllib/...
+
+- label: ":brain: RLlib: Examples {Q/Z}"
+  conditions: ["RAY_CI_RLLIB_AFFECTED"]
+  commands:
+    - cleanup() { if [ "${BUILDKITE_PULL_REQUEST}" = "false" ]; then ./ci/travis/upload_build_info.sh; fi }; trap cleanup EXIT
+    - RLLIB_TESTING=1 ./ci/travis/install-dependencies.sh
     - bazel test --config=ci $(./scripts/bazel_export_options) --build_tests_only
       --test_tag_filters=examples_Q,examples_R,examples_S,examples_T,examples_U,examples_V,examples_W,examples_X,examples_Y,examples_Z,-flaky --test_env=RAY_USE_MULTIPROCESSING_CPU_COUNT=1
       rllib/...
-- label: ":brain: RLlib: rllib/tests/ (A-L)"
+
+- label: ":brain: RLlib: tests/ dir (A-L)"
   conditions: ["RAY_CI_RLLIB_AFFECTED"]
   commands:
     - cleanup() { if [ "${BUILDKITE_PULL_REQUEST}" = "false" ]; then ./ci/travis/upload_build_info.sh; fi }; trap cleanup EXIT
@@ -267,7 +280,7 @@
     - bazel test --config=ci $(./scripts/bazel_export_options) --build_tests_only
       --test_tag_filters=tests_dir_A,tests_dir_B,tests_dir_C,tests_dir_D,tests_dir_E,tests_dir_F,tests_dir_G,tests_dir_H,tests_dir_I,tests_dir_J,tests_dir_K,tests_dir_L,-flaky --test_env=RAY_USE_MULTIPROCESSING_CPU_COUNT=1
       rllib/...
-- label: ":brain: RLlib: rllib/tests/ (M-Z)"
+- label: ":brain: RLlib: tests/ dir (M-Z)"
   conditions: ["RAY_CI_RLLIB_AFFECTED"]
   commands:
     - cleanup() { if [ "${BUILDKITE_PULL_REQUEST}" = "false" ]; then ./ci/travis/upload_build_info.sh; fi }; trap cleanup EXIT
diff --git a/rllib/agents/mock.py b/rllib/agents/mock.py
index 233c5cd48..45e0b1b56 100644
--- a/rllib/agents/mock.py
+++ b/rllib/agents/mock.py
@@ -53,7 +53,7 @@ class _MockTrainer(Trainer):
         self.info = info
         self.restored = True
 
-    def _register_if_needed(self, env_object):
+    def _register_if_needed(self, env_object, config):
         pass
 
     def set_info(self, info):