When encountered an unexpected status, mention it

Instead of just mentioning that something wrong has been found when
parsing UpdateState, also log the value of the erroneous status.

Bug: none
Test: m
Change-Id: I487a115a9347199059a684ef682bec79fa5f26a9
Signed-off-by: Alessio Balsini <balsini@google.com>
diff --git a/fs_mgr/libsnapshot/snapshot.cpp b/fs_mgr/libsnapshot/snapshot.cpp
index 70a69a5..c6b4c95 100644
--- a/fs_mgr/libsnapshot/snapshot.cpp
+++ b/fs_mgr/libsnapshot/snapshot.cpp
@@ -828,7 +828,8 @@
                 cancelled = true;
                 break;
             default:
-                LOG(ERROR) << "Unknown merge status: " << static_cast<uint32_t>(snapshot_state);
+                LOG(ERROR) << "Unknown merge status for \"" << snapshot << "\": "
+                           << "\"" << snapshot_state << "\"";
                 failed = true;
                 break;
         }
@@ -1676,7 +1677,7 @@
     } else if (contents == "merge-failed") {
         return UpdateState::MergeFailed;
     } else {
-        LOG(ERROR) << "Unknown merge state in update state file";
+        LOG(ERROR) << "Unknown merge state in update state file: \"" << contents << "\"";
         return UpdateState::None;
     }
 }
@@ -1698,7 +1699,7 @@
         case UpdateState::MergeFailed:
             return os << "merge-failed";
         default:
-            LOG(ERROR) << "Unknown update state";
+            LOG(ERROR) << "Unknown update state: " << static_cast<uint32_t>(state);
             return os;
     }
 }