Enable tracing of the ion/ion_stat events

These events supersede the ion_heap_grow / ion_heap_shrink events on
4.19+ kernels.

Bug: 154302786
Test: build, run on cuttlefish with new kernel, ls -lZ /sys/kernel/tracing/events/ion/ion_stat/enable
Change-Id: I262d8c3269d4261701361ad4b1bdc322f1f03969
diff --git a/private/genfs_contexts b/private/genfs_contexts
index d4d7fff..b423e64 100644
--- a/private/genfs_contexts
+++ b/private/genfs_contexts
@@ -241,6 +241,7 @@
 genfscon tracefs /events/kmem/rss_stat/                                  u:object_r:debugfs_tracing:s0
 genfscon tracefs /events/kmem/ion_heap_grow/                             u:object_r:debugfs_tracing:s0
 genfscon tracefs /events/kmem/ion_heap_shrink/                           u:object_r:debugfs_tracing:s0
+genfscon tracefs /events/ion/ion_stat/                                   u:object_r:debugfs_tracing:s0
 genfscon tracefs /events/mm_event/mm_event_record/                       u:object_r:debugfs_tracing:s0
 genfscon tracefs /events/oom/oom_score_adj_update/                       u:object_r:debugfs_tracing:s0
 genfscon tracefs /events/task/task_rename/                               u:object_r:debugfs_tracing:s0
@@ -285,6 +286,7 @@
 genfscon debugfs /tracing/events/kmem/rss_stat/                                          u:object_r:debugfs_tracing:s0
 genfscon debugfs /tracing/events/kmem/ion_heap_grow/                                     u:object_r:debugfs_tracing:s0
 genfscon debugfs /tracing/events/kmem/ion_heap_shrink/                                   u:object_r:debugfs_tracing:s0
+genfscon debugfs /tracing/events/ion/ion_stat/                                           u:object_r:debugfs_tracing:s0
 genfscon debugfs /tracing/events/mm_event/mm_event_record/                               u:object_r:debugfs_tracing:s0
 genfscon debugfs /tracing/events/oom/oom_score_adj_update/                               u:object_r:debugfs_tracing:s0
 genfscon debugfs /tracing/events/task/task_rename/                                       u:object_r:debugfs_tracing:s0