add ALLOW_LOCAL_TIDY_TRUE and some tests

* A new ALLOW_LOCAL_TIDY_TRUE variable, default is false.
* If it is 0/false, local "tidy:true" is ignored.
* If it is 1/true, local "tidy:true" is honored as it is now.

Bug: 229779921
Test: make with and without ALLOW_LOCAL_TIDY_TRUE=1
Change-Id: I0323289a4d3bb2514982252a5a1339e94f2bbaab
diff --git a/cc/Android.bp b/cc/Android.bp
index 9103a48..b105e7c 100644
--- a/cc/Android.bp
+++ b/cc/Android.bp
@@ -100,6 +100,7 @@
         "proto_test.go",
         "sanitize_test.go",
         "test_data_test.go",
+        "tidy_test.go",
         "vendor_public_library_test.go",
         "vendor_snapshot_test.go",
     ],