[gnome-shell] RemoteSearch: don't complete a search that was cancelled

[Giovanni Campagna <gcampagna src gnome org>]

commit b0be6b867859cecd6d51a03a3ad92e4ca4d00ef5
Author: Giovanni Campagna <gcampagna gnome org>
Date:   Sun Mar 8 15:32:22 2015 -0700

    RemoteSearch: don't complete a search that was cancelled
    
    This closes a race between setTerms and a slow GetInitialResultSet.
    The bug manifests as follows:
    - initial search for a short string
    - previous results === undefined, call GetInitialResultSet
    - user types more, cancel previous search in setTerms()
    - mainloop, then _gotResults([])
    - previous results === [], !!previous results === true
    - therefore call GetSubsearchResultSet with an empty list of results
    - _gotResults() from GetSubsearchResultSet is empty
    - much later, return from GetInitialResultSet is discarded by
      cancellable
    - user unhappy because what he searched for is not there
    
    After this fix, the flow is:
    - initial search for a short string
    - previous results === undefined, call GetInitialResultSet
    - user types more, cancel previous search in setTerms()
    - mainloop, but no _gotResults
    - previous results === undefined, call GetInitialResultSet again with
      longer string
    - some time later, return from first GetInitialResultSet is discarded
      by cancellable
    - soon after, return from second GetInitialResultSet comes with good
      results
    - user happy
    
    https://bugzilla.gnome.org/show_bug.cgi?id=745861

 js/ui/remoteSearch.js |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)
---
diff --git a/js/ui/remoteSearch.js b/js/ui/remoteSearch.js
index 9ab413e..4fc5000 100644
--- a/js/ui/remoteSearch.js
+++ b/js/ui/remoteSearch.js
@@ -236,8 +236,10 @@ const RemoteSearchProvider = new Lang.Class({
 
     _getResultsFinished: function(results, error, callback) {
         if (error) {
-            if (!error.matches(Gio.IOErrorEnum, Gio.IOErrorEnum.CANCELLED))
-                log('Received error from DBus search provider %s: %s'.format(this.id, String(error)));
+            if (error.matches(Gio.IOErrorEnum, Gio.IOErrorEnum.CANCELLED))
+                return;
+
+            log('Received error from DBus search provider %s: %s'.format(this.id, String(error)));
             callback([]);
             return;
         }