Implementing chrome://thumbnails page to view URLs in TopSites and cached thumbnails.

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 6552f73ac61858267a5a713a0273b79b13442980..284377ff01b9c520ea662533eb3947bd9ce50357 100644
--- a/chrome/browser/history/top_sites_cache.cc
+++ b/chrome/browser/history/top_sites_cache.cc
@@ -6,6 +6,7 @@
 
 #include "base/logging.h"
 #include "base/memory/ref_counted_memory.h"
+#include "url/gurl.h"
 
 namespace history {
 
@@ -30,7 +31,7 @@ Images* TopSitesCache::GetImage(const GURL& url) {
 
 bool TopSitesCache::GetPageThumbnail(
     const GURL& url,
-    scoped_refptr<base::RefCountedMemory>* bytes) {
+    scoped_refptr<base::RefCountedMemory>* bytes) const {
   std::map<GURL, Images>::const_iterator found =
       images_.find(GetCanonicalURL(url));
   if (found != images_.end()) {
@@ -44,7 +45,7 @@ bool TopSitesCache::GetPageThumbnail(
 }
 
 bool TopSitesCache::GetPageThumbnailScore(const GURL& url,
-                                          ThumbnailScore* score) {
+                                          ThumbnailScore* score) const {
   std::map<GURL, Images>::const_iterator found =
       images_.find(GetCanonicalURL(url));
   if (found != images_.end()) {
@@ -54,21 +55,21 @@ bool TopSitesCache::GetPageThumbnailScore(const GURL& url,
   return false;
 }
 
-const GURL& TopSitesCache::GetCanonicalURL(const GURL& url) {
-  CanonicalURLs::iterator i = GetCanonicalURLsIterator(url);
-  return i == canonical_urls_.end() ? url : i->first.first->url;
+const GURL& TopSitesCache::GetCanonicalURL(const GURL& url) const {
+  CanonicalURLs::const_iterator it = GetCanonicalURLsIterator(url);
+  return it == canonical_urls_.end() ? url : it->first.first->url;
 }
 
-const GURL& TopSitesCache::GetCanonicalURLForPrefix(const GURL& url) {
-  CanonicalURLs::iterator i = GetCanonicalURLsIteratorForPrefix(url);
-  return i == canonical_urls_.end() ? url : i->first.first->url;
+const GURL& TopSitesCache::GetCanonicalURLForPrefix(const GURL& url) const {
+  CanonicalURLs::const_iterator it = GetCanonicalURLsIteratorForPrefix(url);
+  return it == canonical_urls_.end() ? url : it->first.first->url;
 }
 
-bool TopSitesCache::IsKnownURL(const GURL& url) {
+bool TopSitesCache::IsKnownURL(const GURL& url) const {
   return GetCanonicalURLsIterator(url) != canonical_urls_.end();
 }
 
-size_t TopSitesCache::GetURLIndex(const GURL& url) {
+size_t TopSitesCache::GetURLIndex(const GURL& url) const {
   DCHECK(IsKnownURL(url));
   return GetCanonicalURLsIterator(url)->second;
 }
@@ -96,8 +97,8 @@ void TopSitesCache::StoreRedirectChain(const RedirectList& redirects,
   }
 }
 
-TopSitesCache::CanonicalURLs::iterator TopSitesCache::GetCanonicalURLsIterator(
-    const GURL& url) {
+TopSitesCache::CanonicalURLs::const_iterator
+    TopSitesCache::GetCanonicalURLsIterator(const GURL& url) const {
   MostVisitedURL most_visited_url;
   most_visited_url.redirects.push_back(url);
   CanonicalURLEntry entry;
@@ -106,8 +107,9 @@ TopSitesCache::CanonicalURLs::iterator TopSitesCache::GetCanonicalURLsIterator(
   return canonical_urls_.find(entry);
 }
 
-TopSitesCache::CanonicalURLs::iterator
-    TopSitesCache::GetCanonicalURLsIteratorForPrefix(const GURL& prefix_url) {
+TopSitesCache::CanonicalURLs::const_iterator
+    TopSitesCache::GetCanonicalURLsIteratorForPrefix(const GURL& prefix_url)
+        const {
   MostVisitedURL most_visited_url;
   most_visited_url.redirects.push_back(prefix_url);
   CanonicalURLEntry entry;
@@ -115,7 +117,7 @@ TopSitesCache::CanonicalURLs::iterator
   entry.second = 0u;
 
   // Perform effective binary search for URL prefix search.
-  TopSitesCache::CanonicalURLs::iterator it =
+  TopSitesCache::CanonicalURLs::const_iterator it =
       canonical_urls_.lower_bound(entry);
   // Perform prefix match.
   if (it != canonical_urls_.end()) {