OsuLogin: Generate AOSP keys and sign APK

Generate keys for the OsuLogin APK and
sign the APK using those keys.

Note that these keys are only used to sign locally-built APKs
during development. They are not release keys.

Bug: 149589553
Test: compiles
Change-Id: I6abee1618faba127dbe0c1618071985a166f6927
diff --git a/packages/OsuLogin/Android.bp b/packages/OsuLogin/Android.bp
index cd9cd1e..d7e36b1 100644
--- a/packages/OsuLogin/Android.bp
+++ b/packages/OsuLogin/Android.bp
@@ -4,9 +4,14 @@
     resource_dirs: ["res"],
     srcs: ["src/**/*.java"],
     sdk_version: "system_current",
-
+    certificate: ":com.android.hotspot2.osulogin.certificate",
     apex_available: [
         "com.android.wifi",
         "test_com.android.wifi",
     ],
 }
+
+android_app_certificate {
+    name: "com.android.hotspot2.osulogin.certificate",
+    certificate: "certs/com.android.hotspot2.osulogin"
+}