Pebble: log some errors during JSON encoding/decoding

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/pebble/PebbleKitSupport.java

@@ -85,7 +85,7 @@ class PebbleKitSupport {
                         sendAppMessageAck(transaction_id);
                         //  }
                     } catch (JSONException e) {
-                        e.printStackTrace();
+                        LOG.error("failed decoding JSON", e);
                     }
                     break;
                 case PEBBLEKIT_ACTION_APP_ACK:

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/pebble/PebbleProtocol.java

@@ -2023,6 +2023,7 @@ public class PebbleProtocol extends GBDeviceProtocol {
                         break;
                 }
             } catch (JSONException e) {
+                LOG.error("error decoding JSON", e);
                 return null;
             }
         }