Removes pinning code from TopSites as we no longer need it.

chrome/common/pref_names.cc

Index: chrome/common/pref_names.cc
diff --git a/chrome/common/pref_names.cc b/chrome/common/pref_names.cc
index 563dd33e3ea5b216f17c75eea7e2d43e952fdad8..2c0c4eab61dee5435fdaef5a82c4d5976444701e 100644
--- a/chrome/common/pref_names.cc
+++ b/chrome/common/pref_names.cc
@@ -1319,10 +1319,6 @@ const char kNtp4IntroDisplayCount[] = "ntp.intro_display_count";
 // New Tab Page URLs that should not be shown as most visited thumbnails.
 const char kNtpMostVisitedURLsBlacklist[] = "ntp.most_visited_blacklist";
 
-// The URLs that have been pinned to the Most Visited section of the New Tab
-// Page.
-const char kNtpMostVisitedPinnedURLs[] = "ntp.pinned_urls";
-
 // Data downloaded from promo resource pages (JSON, RSS) to be used to
 // dynamically deliver data for the new tab page.
 const char kNtpPromoResourceCache[] = "ntp.promo_resource_cache";