Use libgtest_prod_headers.

Test: builds
Bug: 185916167
Change-Id: Ic93ac6bb62c8f5c52f6b5e2f4f5949ba500cc137
diff --git a/cpp/watchdog/server/Android.bp b/cpp/watchdog/server/Android.bp
index 2afee42..a0d85b8 100644
--- a/cpp/watchdog/server/Android.bp
+++ b/cpp/watchdog/server/Android.bp
@@ -40,8 +40,8 @@
         "liblog",
         "libutils",
     ],
-    static_libs: [
-        "libgtest_prod",
+    header_libs: [
+        "libgtest_prod_headers",
     ],
 }