Added a check in Searchbox::OnMostVisitedChanged() to prevent duplicate notifications regarding mos…

chrome/renderer/searchbox/searchbox.cc

Index: chrome/renderer/searchbox/searchbox.cc
diff --git a/chrome/renderer/searchbox/searchbox.cc b/chrome/renderer/searchbox/searchbox.cc
index 1d873975e601c4e1e8fe4a90e35ef3ee56358c63..eb17de17906ff6ef8027905e43ccbb5b4a39144d 100644
--- a/chrome/renderer/searchbox/searchbox.cc
+++ b/chrome/renderer/searchbox/searchbox.cc
@@ -28,6 +28,22 @@ namespace {
 // Size of the results cache.
 const size_t kMaxInstantAutocompleteResultItemCacheSize = 100;
 
+// Returns true if |items_a| and |items_b| are equal.
+bool AreMostVisitedItemsEqual(
+    const std::vector<InstantMostVisitedItem>& items_a,
+    const std::vector<InstantMostVisitedItem>& items_b) {
+  if (items_a.size() != items_b.size())
+    return false;
+
+  for (size_t i = 0; i < items_b.size(); ++i) {
+    if (items_b[i].url != items_a[i].url ||
+        items_b[i].title != items_a[i].title) {
+      return false;
+    }
+  }
+  return true;
+}
+
 }  // namespace
 
 namespace internal {  // for testing
@@ -497,6 +513,19 @@ void SearchBox::SetQuery(const string16& query, bool verbatim) {
 
 void SearchBox::OnMostVisitedChanged(
     const std::vector<InstantMostVisitedItem>& items) {
+  std::vector<InstantMostVisitedItemIDPair> item_id_pairs;
+  GetMostVisitedItems(&item_id_pairs);
+
+  std::vector<InstantMostVisitedItem> last_known_items;
+  for (std::vector<InstantMostVisitedItemIDPair>::const_iterator it =

[samarth, 2013/06/21 20:51:20]

Why bother converting the list? Can't you change AreMostVisitedItemsEqual to
compare the two lists directly?

[kmadhusu, 2013/06/21 21:35:32]

Done.

+           item_id_pairs.begin();
+       it != item_id_pairs.end(); ++it) {
+    last_known_items.push_back(it->second);
+  }
+
+  if (AreMostVisitedItemsEqual(last_known_items, items))
+    return;  // Do not send duplicate onmostvisitedchange events.
+
   most_visited_items_cache_.AddItems(items);
   if (render_view()->GetWebView() && render_view()->GetWebView()->mainFrame()) {
     extensions_v8::SearchBoxExtension::DispatchMostVisitedChanged(