Adding support for forced URLs to TopSites.

chrome/browser/history/top_sites_cache.cc

Index: chrome/browser/history/top_sites_cache.cc
diff --git a/chrome/browser/history/top_sites_cache.cc b/chrome/browser/history/top_sites_cache.cc
index 5914d9910c1966729724223aaad4cd52d0dea75a..4448c89e939bba9484294042cd3078c5cd878e10 100644
--- a/chrome/browser/history/top_sites_cache.cc
+++ b/chrome/browser/history/top_sites_cache.cc
@@ -31,6 +31,7 @@ TopSitesCache::~TopSitesCache() {
 
 void TopSitesCache::SetTopSites(const MostVisitedURLList& top_sites) {
   top_sites_ = top_sites;
+  CountForcedURLs();
   GenerateCanonicalURLs();
 }
 
@@ -119,6 +120,31 @@ size_t TopSitesCache::GetURLIndex(const GURL& url) const {
   return GetCanonicalURLsIterator(url)->second;
 }
 
+size_t TopSitesCache::GetNumNonForcedURLs() const {
+  return top_sites_.size() - num_forced_urls_;
+}
+
+size_t TopSitesCache::GetNumForcedURLs() const {
+  return num_forced_urls_;
+}
+
+void TopSitesCache::CountForcedURLs() {
+  num_forced_urls_ = 0;
+  while (num_forced_urls_ < top_sites_.size()) {
+    // Forced sites are all at the beginning.
+    if (top_sites_[num_forced_urls_].last_forced_time.is_null())
+      break;
+    num_forced_urls_++;
+  }
+  // In debug, ensure the cache user has no forced URLs pass that point.
+  if (DCHECK_IS_ON()) {
+    for (size_t i = num_forced_urls_; i < top_sites_.size(); ++i) {
+      DCHECK(top_sites_[i].last_forced_time.is_null())
+          << "All the forced URLs must appear before non-forced URLs.";
+    }
+  }
+}
+
 void TopSitesCache::GenerateCanonicalURLs() {
   canonical_urls_.clear();
   for (size_t i = 0; i < top_sites_.size(); i++)