[Top Sites] Encoding redirects field in TopSitesDatabase, and adding validations

chrome/browser/history/top_sites_database.h

Index: chrome/browser/history/top_sites_database.h
diff --git a/chrome/browser/history/top_sites_database.h b/chrome/browser/history/top_sites_database.h
index 9659d2a937f97d42fcd823023a0b899d43c1efc6..80e8395ec7072d076cc8c55228f6028ae7010339 100644
--- a/chrome/browser/history/top_sites_database.h
+++ b/chrome/browser/history/top_sites_database.h
@@ -7,6 +7,7 @@
 
 #include <map>
 #include <string>
+#include <vector>
 
 #include "base/gtest_prod_util.h"
 #include "chrome/browser/history/history_types.h"
@@ -57,13 +58,22 @@ class TopSitesDatabase {
   bool RemoveURL(const MostVisitedURL& url);
 
  private:
+  friend class TopSitesDatabaseTest;
   FRIEND_TEST_ALL_PREFIXES(TopSitesDatabaseTest, Version1);
   FRIEND_TEST_ALL_PREFIXES(TopSitesDatabaseTest, Version2);
   FRIEND_TEST_ALL_PREFIXES(TopSitesDatabaseTest, Version3);
+  FRIEND_TEST_ALL_PREFIXES(TopSitesDatabaseTest, Version4);
   FRIEND_TEST_ALL_PREFIXES(TopSitesDatabaseTest, Recovery1);
   FRIEND_TEST_ALL_PREFIXES(TopSitesDatabaseTest, Recovery2);
   FRIEND_TEST_ALL_PREFIXES(TopSitesDatabaseTest, Recovery3);
+  FRIEND_TEST_ALL_PREFIXES(TopSitesDatabaseTest, Recovery4);
   FRIEND_TEST_ALL_PREFIXES(TopSitesDatabaseTest, AddRemoveEditThumbnails);
+  FRIEND_TEST_ALL_PREFIXES(TopSitesDatabaseTest, EncodeCSVString);
+  FRIEND_TEST_ALL_PREFIXES(TopSitesDatabaseTest, DecodeCSVStringSucceed);
+  FRIEND_TEST_ALL_PREFIXES(TopSitesDatabaseTest, DecodeCSVStringFail);
+  FRIEND_TEST_ALL_PREFIXES(TopSitesDatabaseTest, EncodeRedirects);
+  FRIEND_TEST_ALL_PREFIXES(TopSitesDatabaseTest, DecodeRedirects);
+  FRIEND_TEST_ALL_PREFIXES(TopSitesDatabaseTest, DecodeRedirectsFallback);
 
   // Rank of all URLs that are forced and therefore cannot be automatically
   // evicted.
@@ -72,15 +82,33 @@ class TopSitesDatabase {
   // Rank used to indicate that a URL is not stored in the database.
   static const int kRankOfNonExistingURL;
 
-  // Upgrades the thumbnail table to version 3, returning true if the
-  // upgrade was successful.
+  // Upgrades the thumbnail table to version 3, returning true if successful.
   bool UpgradeToVersion3();
 
+  // Upgrades the thumbnail table to version 4, returning true if successful.
+  bool UpgradeToVersion4();
+
   // Adds a new URL to the database.
   void AddPageThumbnail(const MostVisitedURL& url,
                         int new_rank,
                         const Images& thumbnail);
 
+  // Encodes a vector of strings inside a single string, as a comma-separated
+  // list of quoted strings. Quotes are escaped into two quotes.
+  static std::string EncodeCSVString(const std::vector<std::string> str_list);
+
+  // Decodes a string encoded by EncodeCSVString() as a vector of strings,
+  // On success returns true, otherwise returns false and ignores |str_list|.
+  static bool DecodeCSVString(const std::string csv,
+                              std::vector<std::string>* str_list);
+
+  // Encodes |redirects| as string.
+  static std::string EncodeRedirects(const RedirectList& redirects);
+
+  // Decodes a redirects string, appends the result to |redirects|.
+  static void DecodeRedirects(const std::string& encoded_redirects,
+                              RedirectList* redirects);
+
   // Sets the page rank. Should be called within an open transaction.
   void UpdatePageRankNoTransaction(const MostVisitedURL& url, int new_rank);