libsnapshot_test: hardcode alignment. am: 755eb6b606

Original change: https://googleplex-android-review.googlesource.com/c/platform/system/core/+/11870537

Change-Id: Ib020f7ced1fded356d78b4039b054736608fb29e
diff --git a/fs_mgr/libsnapshot/test_helpers.cpp b/fs_mgr/libsnapshot/test_helpers.cpp
index f82a602..de3d912 100644
--- a/fs_mgr/libsnapshot/test_helpers.cpp
+++ b/fs_mgr/libsnapshot/test_helpers.cpp
@@ -52,10 +52,19 @@
 
 bool TestPartitionOpener::GetInfo(const std::string& partition_name,
                                   android::fs_mgr::BlockDeviceInfo* info) const {
-    if (partition_name == "super") {
-        return PartitionOpener::GetInfo(fake_super_path_, info);
+    if (partition_name != "super") {
+        return PartitionOpener::GetInfo(partition_name, info);
     }
-    return PartitionOpener::GetInfo(partition_name, info);
+
+    if (PartitionOpener::GetInfo(fake_super_path_, info)) {
+        // SnapshotUpdateTest uses a relatively small super partition, which requires a small
+        // alignment and 0 offset to work. For the purpose of this test, hardcode the alignment
+        // and offset. This test isn't about testing liblp or libdm.
+        info->alignment_offset = 0;
+        info->alignment = std::min<uint32_t>(info->alignment, static_cast<uint32_t>(128_KiB));
+        return true;
+    }
+    return false;
 }
 
 std::string TestPartitionOpener::GetDeviceString(const std::string& partition_name) const {