Add library verification step (#3436)

Summary:
This is pretty dumb but hopefully good enough to prevent accidental regressions. We simply check if there are "enough" `libevent_core.so`s in the bundle. This is obviously not future-proof but it's super cheap to run and if it causes problems at some point, we can always remove it.

Apologies for the formatting spam. Didn't notice until I submitted this that my editor got a little passive-aggressive.

Pull Request resolved: https://github.com/facebook/flipper/pull/3436

Test Plan: CI here.

Reviewed By: lblasa

Differential Revision: D34210743

Pulled By: passy

fbshipit-source-id: a57c397e39456fae33af9f3ceed08b6944eac79e

scripts/verify-android-libraries.sh

@@ -0,0 +1,17 @@
+#!/usr/bin/env bash
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
+
+BASEDIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )/.." && pwd )"
+NUM=$(unzip -l "$BASEDIR"/android/build/outputs/aar/android-debug.aar | grep -c libevent_core)
+
+if (( NUM >= 4 )); then
+    echo "Found $NUM instances of libevent_core. Looks good."
+    exit 0
+else
+    unzip -l "$BASEDIR"/android/build/outputs/aar/android-debug.aar | grep libevent_core
+    echo "Expected 4 but found $NUM libevent_core.so files. Expecting one for each architecture. See #3395 for details."
+    exit 1
+fi