libsnapshot: log compression algorithm

Log the compression algorithm and compression factor used during OTA for easier debugging

Test: th
Change-Id: Ic50989d7e233983d6299163fc647eb739a0b7cb2
diff --git a/fs_mgr/libsnapshot/libsnapshot_cow/writer_v3.cpp b/fs_mgr/libsnapshot/libsnapshot_cow/writer_v3.cpp
index 1e3fee7..30c5135 100644
--- a/fs_mgr/libsnapshot/libsnapshot_cow/writer_v3.cpp
+++ b/fs_mgr/libsnapshot/libsnapshot_cow/writer_v3.cpp
@@ -121,7 +121,6 @@
         return false;
     }
 
-    LOG(INFO) << "Compression factor: " << header_.max_compression_size;
     num_compress_threads_ = std::max(int(options_.num_compress_threads), 1);
     auto parts = android::base::Split(options_.compression, ",");
     if (parts.size() > 2) {
diff --git a/fs_mgr/libsnapshot/snapshot.cpp b/fs_mgr/libsnapshot/snapshot.cpp
index ba5fb88..cbe8285 100644
--- a/fs_mgr/libsnapshot/snapshot.cpp
+++ b/fs_mgr/libsnapshot/snapshot.cpp
@@ -3242,6 +3242,8 @@
             // Older OTAs don't set an explicit compression type, so default to gz.
             compression_algorithm = "gz";
         }
+        LOG(INFO) << "using compression algorithm: " << compression_algorithm
+                   << ", max compressible block size: " << compression_factor;
     }
 
     PartitionCowCreator cow_creator{