fixes bug 101832 "back/forward buttons should use LOAD_NORMAL + VALIDATE_NEVER"

r=gagan, sr=rpotts

docshell/base/nsDocShell.cpp

@@ -4769,6 +4769,9 @@ nsresult nsDocShell::DoChannelLoad(nsIChannel * aChannel,
     // Load attributes depend on load type...
     switch (mLoadType) {
     case LOAD_HISTORY:
+        loadFlags |= nsIRequest::VALIDATE_NEVER;
+        break;
+
     case LOAD_RELOAD_CHARSET_CHANGE:
         loadFlags |= nsIRequest::LOAD_FROM_CACHE;
         break;
@@ -4782,6 +4785,7 @@ nsresult nsDocShell::DoChannelLoad(nsIChannel * aChannel,
     case LOAD_REFRESH:
         loadFlags |= nsIRequest::LOAD_BYPASS_CACHE;
         break;
+
     case LOAD_NORMAL:
     case LOAD_LINK:
         // Set cache checking flags