Make ziparchive-tests run standalone.

We need to (a) tell soong to copy our data and (b) automatically find
our data relative to our executable.

The real point of this is to be able to run these tests in APCT and
presubmit.

Bug: N/A
Test: ran tests on host and device, from a variety of directories
Change-Id: I4c0be1ac60f03953fdd5ba6e3d15b1aaa37ed019
diff --git a/Android.bp b/Android.bp
index ed1b9bc..6c06618 100644
--- a/Android.bp
+++ b/Android.bp
@@ -93,6 +93,10 @@
     host_supported: true,
     defaults: ["libziparchive_flags"],
 
+    data: [
+        "testdata/**/*",
+    ],
+
     srcs: [
         "entry_name_utils_test.cc",
         "zip_archive_test.cc",