InstantExtended: Prevent spurious themechanged/mostvisitedchanged events

chrome/renderer/searchbox/searchbox.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/renderer/searchbox/searchbox.h"
 
 #include "base/string_number_conversions.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/omnibox_focus_state.h"
 #include "chrome/common/render_messages.h"
 #include "chrome/common/url_constants.h"
 #include "chrome/renderer/searchbox/searchbox_extension.h"
 #include "content/public/renderer/render_view.h"
 #include "grit/renderer_resources.h"
 #include "net/base/escape.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebDocument.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebFrame.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebView.h"
 #include "ui/base/resource/resource_bundle.h"
 
 namespace {
 
 // Size of the results cache.
 const size_t kMaxInstantAutocompleteResultItemCacheSize = 100;
 
+bool IsThemeInfoEqual(const ThemeBackgroundInfo& new_theme_info,
+    const ThemeBackgroundInfo& old_theme_info) {
+  return old_theme_info.color_r == new_theme_info.color_r &&
+      old_theme_info.color_g == new_theme_info.color_g &&
+      old_theme_info.color_b == new_theme_info.color_b &&
+      old_theme_info.color_a == new_theme_info.color_a &&
+      old_theme_info.theme_id == new_theme_info.theme_id &&
+      old_theme_info.image_horizontal_alignment ==
+          new_theme_info.image_horizontal_alignment &&
+      old_theme_info.image_vertical_alignment ==
+          new_theme_info.image_vertical_alignment &&
+      old_theme_info.image_tiling == new_theme_info.image_tiling &&
+      old_theme_info.image_height == new_theme_info.image_height &&
+      old_theme_info.has_attribution == new_theme_info.has_attribution;
+}
+
+bool AreMostVisitedItemsEqual(
+    const std::vector<InstantMostVisitedItemIDPair>& new_items,
+    const std::vector<InstantMostVisitedItemIDPair>& old_items) {
+  if (old_items.size() != new_items.size())
+    return false;
+  for (size_t i = 0; i < new_items.size(); i++) {
+    const InstantMostVisitedItem& old_item = old_items[i].second;
+    const InstantMostVisitedItem& new_item = new_items[i].second;
+    if (new_item.url != old_item.url || new_item.title != old_item.title)
+      return false;
+  }
+  return true;
+}
+
 }  // namespace
 
 SearchBox::SearchBox(content::RenderView* render_view)
     : content::RenderViewObserver(render_view),
       content::RenderViewObserverTracker<SearchBox>(render_view),
       verbatim_(false),
       query_is_restricted_(false),
       selection_start_(0),
       selection_end_(0),
       start_margin_(0),
@@ skipping 285 matching lines @@
     extensions_v8::SearchBoxExtension::DispatchKeyCaptureChange(
         render_view()->GetWebView()->mainFrame());
   }
 }
 
 void SearchBox::OnSetDisplayInstantResults(bool display_instant_results) {
   display_instant_results_ = display_instant_results;
 }
 
 void SearchBox::OnThemeChanged(const ThemeBackgroundInfo& theme_info) {
+  if (IsThemeInfoEqual(theme_info, theme_info_))
+    return;
   theme_info_ = theme_info;
   if (render_view()->GetWebView() && render_view()->GetWebView()->mainFrame()) {
     extensions_v8::SearchBoxExtension::DispatchThemeChange(
         render_view()->GetWebView()->mainFrame());
   }
 }
 
 void SearchBox::OnFontInformationReceived(const string16& omnibox_font,
                                           size_t omnibox_font_size) {
   omnibox_font_ = omnibox_font;
@@ skipping 28 matching lines @@
 }
 
 void SearchBox::SetQuery(const string16& query, bool verbatim) {
   query_ = query;
   verbatim_ = verbatim;
   query_is_restricted_ = false;
 }
 
 void SearchBox::OnMostVisitedChanged(
     const std::vector<InstantMostVisitedItemIDPair>& items) {
+  std::vector<InstantMostVisitedItemIDPair> old_items;
+  most_visited_items_cache_.GetCurrentItems(&old_items);
+  if (AreMostVisitedItemsEqual(items, old_items))
+    return;
+
   most_visited_items_cache_.AddItemsWithRestrictedID(items);
 
   if (render_view()->GetWebView() && render_view()->GetWebView()->mainFrame()) {
     extensions_v8::SearchBoxExtension::DispatchMostVisitedChanged(
         render_view()->GetWebView()->mainFrame());
   }
 }
 
 void SearchBox::GetMostVisitedItems(
     std::vector<InstantMostVisitedItemIDPair>* items) const {
   return most_visited_items_cache_.GetCurrentItems(items);
 }
 
 bool SearchBox::GetMostVisitedItemWithID(
     InstantRestrictedID most_visited_item_id,
     InstantMostVisitedItem* item) const {
   return most_visited_items_cache_.GetItemWithRestrictedID(most_visited_item_id,
                                                            item);
 }