Ensure using chrome://thumb2/... adds the URL as a forced URL in TopSites so that a thumbnail is ca…

chrome/browser/history/top_sites_impl.cc

Index: chrome/browser/history/top_sites_impl.cc
diff --git a/chrome/browser/history/top_sites_impl.cc b/chrome/browser/history/top_sites_impl.cc
index 9eb3a00694f7a060f98cdb30e5dfadc134aca212..40f78fce1bd49afb2299049a584dc73725f7eefb 100644
--- a/chrome/browser/history/top_sites_impl.cc
+++ b/chrome/browser/history/top_sites_impl.cc
@@ -607,6 +607,39 @@ bool TopSitesImpl::loaded() const {
   return loaded_;
 }
 
+bool TopSitesImpl::AddForcedURL(const GURL& url, const base::Time& time) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  size_t num_forced = cache_->GetNumForcedURLs();
+  MostVisitedURLList new_list(cache_->top_sites());
+  MostVisitedURL new_url;
+
+  if (cache_->IsKnownURL(url)) {
+    size_t index = cache_->GetURLIndex(url);
+    // Do nothing if we currently have that URL as non-forced.
+    if (new_list[index].last_forced_time.is_null())
+      return false;
+
+    // Update the |last_forced_time| of the already existing URL. Delete it and
+    // reinsert it at the right location.
+    new_url = new_list[index];
+    new_list.erase(new_list.begin() + index);
+    num_forced--;
+  } else {
+    new_url.url = url;
+    new_url.redirects.push_back(url);
+  }
+  new_url.last_forced_time = time;
+  // Add forced URLs and sort. Added to the end of the list of forced URLs
+  // since this is almost always where it needs to go, unless the user's local
+  // clock is fiddled with.
+  MostVisitedURLList::iterator mid = new_list.begin() + num_forced;
+  new_list.insert(mid, new_url);
+  mid = new_list.begin() + num_forced;  // Mid was invalidated.
+  std::inplace_merge(new_list.begin(), mid, mid + 1, ForcedURLComparator);
+  SetTopSites(new_list);
+  return true;
+}
+
 bool TopSitesImpl::AddPrepopulatedPages(MostVisitedURLList* urls,
                                         size_t num_forced_urls) {
   bool added = false;