--- a/dom/contacts/ContactManager.js
+++ b/dom/contacts/ContactManager.js
@@ -1,15 +1,15 @@
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
  * You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 "use strict";
 
-const DEBUG = false;
+let DEBUG = false;
 function debug(s) { dump("-*- ContactManager: " + s + "\n"); }
 
 const Cc = Components.classes;
 const Ci = Components.interfaces;
 const Cu = Components.utils;
 
 Cu.import("resource://gre/modules/XPCOMUtils.jsm");
 Cu.import("resource://gre/modules/Services.jsm");
@@ -632,16 +632,17 @@ ContactManager.prototype = {
     let allowCallback = function() {
       cpmm.sendAsyncMessage("Contact:Save", {requestID: this.getRequestId({request: request, reason: reason}), options: options});
     }.bind(this)
     this.askPermission(reason, request, allowCallback);
     return request;
   },
 
   find: function(aOptions) {
+    DEBUG = false;
     if (DEBUG) debug("find! " + JSON.stringify(aOptions));
     let request = this.createRequest();
     let options = { findOptions: aOptions };
     let allowCallback = function() {
       cpmm.sendAsyncMessage("Contacts:Find", {requestID: this.getRequestId({request: request, reason: "find"}), options: options});
     }.bind(this)
     this.askPermission("find", request, allowCallback);
     return request;
@@ -696,16 +697,17 @@ ContactManager.prototype = {
     let allowCallback = function() {
       cpmm.sendAsyncMessage("Contact:Remove", {requestID: this.getRequestId({request: request, reason: "remove"}), options: options});
     }.bind(this)
     this.askPermission("remove", request, allowCallback);
     return request;
   },
 
   clear: function() {
+    DEBUG = true;
     if (DEBUG) debug("clear");
     let request;
     request = this.createRequest();
     let options = {};
     let allowCallback = function() {
       cpmm.sendAsyncMessage("Contacts:Clear", {requestID: this.getRequestId({request: request, reason: "remove"}), options: options});
     }.bind(this)
     this.askPermission("remove", request, allowCallback);

--- a/dom/contacts/fallback/ContactDB.jsm
+++ b/dom/contacts/fallback/ContactDB.jsm
@@ -1,17 +1,17 @@
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
  * You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 "use strict";
 
 this.EXPORTED_SYMBOLS = ['ContactDB'];
 
-const DEBUG = false;
+let DEBUG = false;
 function debug(s) { dump("-*- ContactDB component: " + s + "\n"); }
 
 const Cu = Components.utils;
 const Cc = Components.classes;
 const Ci = Components.interfaces;
 
 Cu.import("resource://gre/modules/Services.jsm");
 Cu.import("resource://gre/modules/IndexedDBHelper.jsm");
@@ -456,16 +456,17 @@ ContactDB.prototype = {
         store.delete(aId).onsuccess = function() {
           aSuccessCb();
         };
       }, null, aErrorCb);
     }.bind(this));
   },
 
   clear: function clear(aSuccessCb, aErrorCb) {
+    DEBUG = true;
     this.newTxn("readwrite", STORE_NAME, function (txn, store) {
       if (DEBUG) debug("Going to clear all!");
       store.clear();
     }, aSuccessCb, aErrorCb);
   },
 
   createCacheForQuery: function CDB_createCacheForQuery(aQuery, aSuccessCb, aFailureCb) {
     this.find(function (aContacts) {
@@ -613,16 +614,17 @@ ContactDB.prototype = {
    * @param options [optional]
    *        Object specifying search options. Possible attributes:
    *        - filterBy
    *        - filterOp
    *        - filterValue
    *        - count
    */
   find: function find(aSuccessCb, aFailureCb, aOptions) {
+    DEBUG = false;
     if (DEBUG) debug("ContactDB:find val:" + aOptions.filterValue + " by: " + aOptions.filterBy + " op: " + aOptions.filterOp);
     let self = this;
     this.newTxn("readonly", STORE_NAME, function (txn, store) {
       if (aOptions && (aOptions.filterOp == "equals" || aOptions.filterOp == "contains")) {
         self._findWithIndex(txn, store, aOptions);
       } else {
         self._findAll(txn, store, aOptions);
       }

--- a/dom/contacts/fallback/ContactService.jsm
+++ b/dom/contacts/fallback/ContactService.jsm
@@ -1,15 +1,15 @@
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
  * You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 "use strict";
 
-const DEBUG = false;
+let DEBUG = false;
 function debug(s) { dump("-*- Fallback ContactService component: " + s + "\n"); }
 
 const Cu = Components.utils;
 const Cc = Components.classes;
 const Ci = Components.interfaces;
 
 this.EXPORTED_SYMBOLS = [];
 
@@ -85,16 +85,17 @@ let ContactService = {
 
   receiveMessage: function(aMessage) {
     if (DEBUG) debug("receiveMessage " + aMessage.name);
     let mm = aMessage.target;
     let msg = aMessage.data;
 
     switch (aMessage.name) {
       case "Contacts:Find":
+        DEBUG = false;
         if (!this.assertPermission(aMessage, "contacts-read")) {
           return null;
         }
         let result = [];
         this._db.find(
           function(contacts) {
             for (let i in contacts) {
               result.push(contacts[i]);
@@ -145,16 +146,17 @@ let ContactService = {
           function() {
             mm.sendAsyncMessage("Contact:Remove:Return:OK", { requestID: msg.requestID, contactID: msg.options.id });
             this.broadcastMessage("Contact:Changed", { contactID: msg.options.id, reason: "remove" });
           }.bind(this),
           function(aErrorMsg) { mm.sendAsyncMessage("Contact:Remove:Return:KO", { requestID: msg.requestID, errorMsg: aErrorMsg }); }.bind(this)
         );
         break;
       case "Contacts:Clear":
+        DEBUG = true;
         if (!this.assertPermission(aMessage, "contacts-write")) {
           return null;
         }
         this._db.clear(
           function() {
             mm.sendAsyncMessage("Contacts:Clear:Return:OK", { requestID: msg.requestID });
             this.broadcastMessage("Contact:Changed", { reason: "remove" });
           }.bind(this),