Removed dead code from chrome/browser/extensions/api/web_navigation

chrome/browser/extensions/api/web_navigation/frame_navigation_state.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/extensions/api/web_navigation/frame_navigation_state.h"
 
 #include "base/logging.h"
 #include "chrome/common/url_constants.h"
 #include "extensions/common/constants.h"
 
@@ skipping 19 matching lines @@
       render_view_host(NULL) {
 }
 
 FrameNavigationState::FrameID::FrameID(
     int64 frame_num,
     content::RenderViewHost* render_view_host)
     : frame_num(frame_num),
       render_view_host(render_view_host) {
 }
 
-bool FrameNavigationState::FrameID::IsValid() const {
-  return frame_num >= 0 && render_view_host;
-}
-
 bool FrameNavigationState::FrameID::operator<(
     const FrameNavigationState::FrameID& other) const {
   return frame_num < other.frame_num ||
       (frame_num == other.frame_num &&
        render_view_host < other.render_view_host);
 }
 
 bool FrameNavigationState::FrameID::operator==(
     const FrameNavigationState::FrameID& other) const {
   return frame_num == other.frame_num &&
@@ skipping 166 matching lines @@
 }
 
 bool FrameNavigationState::GetIsServerRedirected(FrameID frame_id) const {
   FrameIdToStateMap::const_iterator frame_state =
       frame_state_map_.find(frame_id);
   return (frame_state != frame_state_map_.end() &&
           frame_state->second.is_server_redirected);
 }
 
 }  // namespace extensions