DevTools: simplify http handler delegate as it is moving into content.

chromecast/browser/devtools/cast_dev_tools_delegate.cc

 // Copyright 2014 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 "chromecast/browser/devtools/cast_dev_tools_delegate.h"
 
 #include "base/macros.h"
 #include "build/build_config.h"
 #include "grit/shell_resources.h"
 #include "ui/base/resource/resource_bundle.h"
@@ skipping 16 matching lines @@
   return ResourceBundle::GetSharedInstance().GetRawDataResource(
       IDR_CAST_SHELL_DEVTOOLS_DISCOVERY_PAGE).as_string();
 #endif  // defined(OS_ANDROID)
 }
 
 std::string CastDevToolsDelegate::GetFrontendResource(
     const std::string& path) {
   return std::string();
 }
 
-std::string CastDevToolsDelegate::GetPageThumbnailData(const GURL& url) {
-  return std::string();
-}
-
-content::DevToolsExternalAgentProxyDelegate*
-CastDevToolsDelegate::HandleWebSocketConnection(const std::string& path) {
-  return nullptr;
-}
-
 }  // namespace shell
 }  // namespace chromecast