Remove unused constant kBackForwardNavigationScheme.

BUG=none
TEST=none

Review URL: http://codereview.chromium.org/7633053

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@96863 0039d316-1c4b-4281-b951-d872f2087c98

content/renderer/render_view.cc

@@ -261,8 +261,6 @@ static const int kDelaySecondsForContentStateSync = 1;
 // The maximum number of popups that can be spawned from one page.
 static const int kMaximumNumberOfUnacknowledgedPopups = 25;
 
-static const char kBackForwardNavigationScheme[] = "history";
-
 static void GetRedirectChain(WebDataSource* ds, std::vector<GURL>* result) {
   WebVector<WebURL> urls;
   ds->redirectChain(urls);