Enable Java in mixed builds.

Allowlist manual BUILD files in prebuilts/bazel for
the toolchain setup.

Test: b build build/bazel/examples/java/...
Change-Id: Id649dce631731e5396da4a9fe224e33f8949dd7d
Bug: 196441639
diff --git a/android/allowlists/allowlists.go b/android/allowlists/allowlists.go
index af82942..ab71d99 100644
--- a/android/allowlists/allowlists.go
+++ b/android/allowlists/allowlists.go
@@ -257,6 +257,7 @@
 		"packages/apps/QuickSearchBox":/* recursive = */ true,
 		"packages/apps/WallpaperPicker":/* recursive = */ false,
 
+		"prebuilts/bazel":/* recursive = */ true,
 		"prebuilts/bundletool":/* recursive = */ true,
 		"prebuilts/gcc":/* recursive = */ true,
 		"prebuilts/build-tools":/* recursive = */ true,