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/OWNERS b/cc/OWNERS
index a438b15..ffbf14a 100644
--- a/cc/OWNERS
+++ b/cc/OWNERS
@@ -1,4 +1,4 @@
 per-file ndk_*.go = danalbert@google.com
-per-file tidy.go = srhines@google.com, chh@google.com
+per-file tidy*.go = srhines@google.com, chh@google.com
 per-file afdo.go,afdo_test.go,lto.go,pgo.go = srhines@google.com, pirama@google.com, yikong@google.com
 per-file coverage.go = pirama@google.com, srhines@google.com, allenhair@google.com