--- a/toolkit/components/places/Helpers.cpp
+++ b/toolkit/components/places/Helpers.cpp
@@ -242,17 +242,17 @@ GenerateRandomBytes(uint32_t aSize,
     }
     (void)PR_Close(urandom);
   }
   return rv;
 #endif
 }
 
 nsresult
-GenerateGUID(nsCString& _guid)
+GenerateGUID(nsACString& _guid)
 {
   _guid.Truncate();
 
   // Request raw random bytes and base64url encode them.  For each set of three
   // bytes, we get one character.
   const uint32_t kRequiredBytesLength =
     static_cast<uint32_t>(GUID_LENGTH / 4 * 3);
 

--- a/toolkit/components/places/Helpers.h
+++ b/toolkit/components/places/Helpers.h
@@ -132,17 +132,17 @@ void GetReversedHostname(const nsString&
  */
 void ReverseString(const nsString& aInput, nsString& aReversed);
 
 /**
  * Generates an 12 character guid to be used by bookmark and history entries.
  *
  * @note This guid uses the characters a-z, A-Z, 0-9, '-', and '_'.
  */
-nsresult GenerateGUID(nsCString& _guid);
+nsresult GenerateGUID(nsACString& _guid);
 
 /**
  * Determines if the string is a valid guid or not.
  *
  * @param aGUID
  *        The guid to test.
  * @return true if it is a valid guid, false otherwise.
  */

--- a/toolkit/components/places/nsINavHistoryService.idl
+++ b/toolkit/components/places/nsINavHistoryService.idl
@@ -1439,16 +1439,23 @@ interface nsINavHistoryService : nsISupp
    * history is disabled if the places.history.enabled pref is false.
    */
   readonly attribute boolean historyDisabled;
 
   /**
    * Clear all TRANSITION_EMBED visits.
    */
   void clearEmbedVisits();
+
+  /**
+   * Generate a guid.
+   * Guids can be used for any places purposes (history, bookmarks, etc.)
+   * Returns null if the generation of the guid failed.
+   */
+  ACString makeGuid();
 };
 
 /**
  * @see runInBatchMode of nsINavHistoryService/nsINavBookmarksService
  */
 [scriptable, function, uuid(5a5a9154-95ac-4e3d-90df-558816297407)]
 interface nsINavHistoryBatchCallback : nsISupports {
   void runBatched(in nsISupports aUserData);

--- a/toolkit/components/places/nsNavHistory.cpp
+++ b/toolkit/components/places/nsNavHistory.cpp
@@ -435,17 +435,16 @@ nsNavHistory::GetOrCreateIdForPage(nsIUR
   rv = stmt->BindInt32ByName(NS_LITERAL_CSTRING("hidden"), 1);
   NS_ENSURE_SUCCESS(rv, rv);
   nsAutoCString spec;
   rv = aURI->GetSpec(spec);
   NS_ENSURE_SUCCESS(rv, rv);
   rv = stmt->BindInt32ByName(NS_LITERAL_CSTRING("frecency"),
                              IsQueryURI(spec) ? 0 : -1);
   NS_ENSURE_SUCCESS(rv, rv);
-  nsAutoCString guid;
   rv = GenerateGUID(_GUID);
   NS_ENSURE_SUCCESS(rv, rv);
   rv = stmt->BindUTF8StringByName(NS_LITERAL_CSTRING("guid"), _GUID);
   NS_ENSURE_SUCCESS(rv, rv);
 
   rv = stmt->Execute();
   NS_ENSURE_SUCCESS(rv, rv);
 
@@ -3718,16 +3717,25 @@ nsNavHistory::clearEmbedVisits() {
 }
 
 NS_IMETHODIMP
 nsNavHistory::ClearEmbedVisits() {
   clearEmbedVisits();
   return NS_OK;
 }
 
+NS_IMETHODIMP
+nsNavHistory::MakeGuid(nsACString& aGuid) {
+  if (NS_FAILED(GenerateGUID(aGuid))) {
+    MOZ_ASSERT(false, "Shouldn't fail to create a guid!");
+    aGuid.SetIsVoid(true);
+  }
+  return NS_OK;
+}
+
 // nsNavHistory::CheckIsRecentEvent
 //
 //    Sees if this URL happened "recently."
 //
 //    It is always removed from our recent list no matter what. It only counts
 //    as "recent" if the event happened more recently than our event
 //    threshold ago.