Move some content url constants to /url.

chrome/browser/history/in_memory_url_index.cc

Index: chrome/browser/history/in_memory_url_index.cc
diff --git a/chrome/browser/history/in_memory_url_index.cc b/chrome/browser/history/in_memory_url_index.cc
index 71a58c8ef011cde61ffe72c0933728eaca8523f0..05a04be49b2337f32240f6f5ceb154ae64920d32 100644
--- a/chrome/browser/history/in_memory_url_index.cc
+++ b/chrome/browser/history/in_memory_url_index.cc
@@ -40,11 +40,11 @@ void InitializeSchemeWhitelist(std::set<std::string>* whitelist) {
     return;  // Nothing to do, already initialized.
   whitelist->insert(std::string(content::kAboutScheme));
   whitelist->insert(std::string(content::kChromeUIScheme));
-  whitelist->insert(std::string(content::kFileScheme));
-  whitelist->insert(std::string(content::kFtpScheme));
+  whitelist->insert(std::string(url::kFileScheme));
+  whitelist->insert(std::string(url::kFtpScheme));
   whitelist->insert(std::string(url::kHttpScheme));
   whitelist->insert(std::string(url::kHttpsScheme));
-  whitelist->insert(std::string(content::kMailToScheme));
+  whitelist->insert(std::string(url::kMailToScheme));
 }
 
 // Restore/SaveCacheObserver ---------------------------------------------------