Update the "host" bionic code tzdata lookup logic

The "if defined(__ANDROID__)" else branch is there to support
bionic when running on host environments.

The code now checks the
${ANDROID_RUNTIME_ROOT}/etc/tz/tzdata path as well.

This is similar to the current on-device expectations.

Eventually, we may remove the /system / ANDROID_ROOT cases.

Bug: 119293618
Test: build only
Change-Id: I8310f7b5a1c14567a648673970c636c7c84ff818
diff --git a/libc/tzcode/bionic.cpp b/libc/tzcode/bionic.cpp
index cb9c359..9051308 100644
--- a/libc/tzcode/bionic.cpp
+++ b/libc/tzcode/bionic.cpp
@@ -228,13 +228,18 @@
   if (fd >= 0) return fd;
 #else
   // On the host, we don't expect those locations to exist, and we're not
-  // worried about security so we trust $ANDROID_DATA and $ANDROID_ROOT to
-  // point us in the right direction.
+  // worried about security so we trust $ANDROID_DATA, $ANDROID_RUNTIME_ROOT
+  // and $ANDROID_ROOT to point us in the right direction.
   char* path = make_path("ANDROID_DATA", "/misc/zoneinfo/current/tzdata");
   fd = __bionic_open_tzdata_path(path, olson_id, entry_length);
   free(path);
   if (fd >= 0) return fd;
 
+  path = make_path("ANDROID_RUNTIME_ROOT", "/etc/tz/tzdata");
+  fd = __bionic_open_tzdata_path(path, olson_id, entry_length);
+  free(path);
+  if (fd >= 0) return fd;
+
   path = make_path("ANDROID_ROOT", "/usr/share/zoneinfo/tzdata");
   fd = __bionic_open_tzdata_path(path, olson_id, entry_length);
   free(path);