Filter redundant JumpList favicons' fetching and related

chrome/browser/win/jumplist.cc

Index: chrome/browser/win/jumplist.cc
diff --git a/chrome/browser/win/jumplist.cc b/chrome/browser/win/jumplist.cc
index 74abc8c6c0affafb89b3d9280a6c4d94278756f1..1e50ff80ebf8939e4f3742b319feb6c2292d06a0 100644
--- a/chrome/browser/win/jumplist.cc
+++ b/chrome/browser/win/jumplist.cc
@@ -441,6 +441,8 @@ void JumpList::CancelPendingUpdate() {
 
 void JumpList::Terminate() {
   DCHECK(CalledOnValidThread());
+  timer_most_visited_.Stop();
+  timer_recently_closed_.Stop();
   CancelPendingUpdate();
   if (profile_) {
     sessions::TabRestoreService* tab_restore_service =
@@ -464,14 +466,16 @@ void JumpList::ShutdownOnUIThread() {
 void JumpList::OnMostVisitedURLsAvailable(
     const history::MostVisitedURLList& urls) {
   DCHECK(CalledOnValidThread());
-  // If we have a pending favicon request, cancel it here (it is out of date).
-  CancelPendingUpdate();
 
+  // At most 9 JumpList items can be displayed for the "Most Visited"
+  // category.
+  const int kMostVistedCount = 9;
   {
     JumpListData* data = &jumplist_data_->data;
     base::AutoLock auto_lock(data->list_lock_);
     data->most_visited_pages_.clear();
-    for (size_t i = 0; i < urls.size(); i++) {
+
+    for (size_t i = 0; i < urls.size() && i < kMostVistedCount; i++) {
       const history::MostVisitedURL& url = urls[i];
       scoped_refptr<ShellLinkItem> link = CreateShellLink();
       std::string url_string = url.url.spec();
@@ -492,9 +496,26 @@ void JumpList::OnMostVisitedURLsAvailable(
 
 void JumpList::TabRestoreServiceChanged(sessions::TabRestoreService* service) {
   DCHECK(CalledOnValidThread());
+
   // if we have a pending favicon request, cancel it here (it is out of date).
   CancelPendingUpdate();
 
+  // Initialize the one-shot timer to update the the "Recently Closed" category
+  // in a while. If there is already a request queued then cancel it and post
+  // the new request. This ensures that JumpList update of the "Recently Closed"
+  // category won't happen until there has been a brief quiet period, thus
+  // avoiding update storms.
+  if (timer_recently_closed_.IsRunning()) {
+    timer_recently_closed_.Reset();
+  } else {
+    timer_recently_closed_.Start(
+        FROM_HERE, kDelayForJumplistUpdate,
+        base::Bind(&JumpList::DeferredTabRestoreServiceChanged,
+                   base::Unretained(this)));
+  }
+}
+
+void JumpList::DeferredTabRestoreServiceChanged() {
   // Create a list of ShellLinkItems from the "Recently Closed" pages.
   // As noted above, we create a ShellLinkItem objects with the following
   // parameters.
@@ -516,6 +537,8 @@ void JumpList::TabRestoreServiceChanged(sessions::TabRestoreService* service) {
     data->recently_closed_pages_.clear();
 
     for (const auto& entry : tab_restore_service->entries()) {
+      if (data->recently_closed_pages_.size() >= kRecentlyClosedCount)
+        break;
       switch (entry->type) {
         case sessions::TabRestoreService::TAB:
           AddTab(static_cast<const sessions::TabRestoreService::Tab&>(*entry),
@@ -661,22 +684,6 @@ void JumpList::PostRunUpdate() {
   DCHECK(CalledOnValidThread());
 
   TRACE_EVENT0("browser", "JumpList::PostRunUpdate");
-  // Initialize the one-shot timer to update the jumplists in a while.
-  // If there is already a request queued then cancel it and post the new
-  // request. This ensures that JumpListUpdates won't happen until there has
-  // been a brief quiet period, thus avoiding update storms.
-  if (timer_.IsRunning()) {
-    timer_.Reset();
-  } else {
-    timer_.Start(FROM_HERE, kDelayForJumplistUpdate, this,
-                 &JumpList::DeferredRunUpdate);
-  }
-}
-
-void JumpList::DeferredRunUpdate() {
-  DCHECK(CalledOnValidThread());
-
-  TRACE_EVENT0("browser", "JumpList::DeferredRunUpdate");
   // Check if incognito windows (or normal windows) are disabled by policy.
   IncognitoModePrefs::Availability incognito_availability =
       profile_ ? IncognitoModePrefs::GetAvailability(profile_->GetPrefs())
@@ -708,8 +715,30 @@ void JumpList::TopSitesLoaded(history::TopSites* top_sites) {
 
 void JumpList::TopSitesChanged(history::TopSites* top_sites,
                                ChangeReason change_reason) {
-  top_sites->GetMostVisitedURLs(
-      base::Bind(&JumpList::OnMostVisitedURLsAvailable,
-                 weak_ptr_factory_.GetWeakPtr()),
-      false);
+  // If we have a pending favicon request, cancel it here (it is out of date).
+  CancelPendingUpdate();
+
+  // Initialize the one-shot timer to update the the "Most visited" category in
+  // a while. If there is already a request queued then cancel it and post the
+  // new request. This ensures that JumpList update of the "Most visited"
+  // category won't happen until there has been a brief quiet period, thus
+  // avoiding update storms.
+  if (timer_most_visited_.IsRunning()) {
+    timer_most_visited_.Reset();
+  } else {
+    timer_most_visited_.Start(
+        FROM_HERE, kDelayForJumplistUpdate,
+        base::Bind(&JumpList::DeferredTopSitesChanged, base::Unretained(this)));
+  }
+}
+
+void JumpList::DeferredTopSitesChanged() {
+  scoped_refptr<history::TopSites> top_sites =
+      TopSitesFactory::GetForProfile(profile_);
+  if (top_sites) {
+    top_sites->GetMostVisitedURLs(
+        base::Bind(&JumpList::OnMostVisitedURLsAvailable,
+                   weak_ptr_factory_.GetWeakPtr()),
+        false);
+  }
 }