blockchain: avoid exceptions in output verification

This can happen if we get a bad tx, so let's not spam the log.

src/cryptonote_core/blockchain.cpp

@@ -188,7 +188,12 @@ bool Blockchain::scan_outputkeys_for_indexes(size_t tx_version, const txin_to_ke
   {
     try
     {
-      m_db->get_output_key(tx_in_to_key.amount, absolute_offsets, outputs);
+      m_db->get_output_key(tx_in_to_key.amount, absolute_offsets, outputs, true);
+      if (absolute_offsets.size() != outputs.size())
+      {
+        MERROR_VER("Output does not exist! amount = " << tx_in_to_key.amount);
+        return false;
+      }
     }
     catch (...)
     {
@@ -208,7 +213,12 @@ bool Blockchain::scan_outputkeys_for_indexes(size_t tx_version, const txin_to_ke
         add_offsets.push_back(absolute_offsets[i]);
       try
       {
-        m_db->get_output_key(tx_in_to_key.amount, add_offsets, add_outputs);
+        m_db->get_output_key(tx_in_to_key.amount, add_offsets, add_outputs, true);
+        if (add_offsets.size() != add_outputs.size())
+        {
+          MERROR_VER("Output does not exist! amount = " << tx_in_to_key.amount);
+          return false;
+        }
       }
       catch (...)
       {