Use blueprint/pool

Use blueprint's typesafe sync.Pool.

Test: builds
Change-Id: I3de1c455f229eb23ac3ca3dc0baa3bdd7bc0d5d6
diff --git a/android/Android.bp b/android/Android.bp
index 540d65b..aef18fe 100644
--- a/android/Android.bp
+++ b/android/Android.bp
@@ -11,6 +11,7 @@
         "blueprint-depset",
         "blueprint-gobtools",
         "blueprint-metrics",
+        "blueprint-pool",
         "sbox_proto",
         "soong",
         "soong-android_team_proto",