Make URLDataSource::GetSource() const.

chrome/browser/search/local_omnibox_popup_source.cc

 // Copyright 2013 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/search/local_omnibox_popup_source.h"
 
 #include "base/logging.h"
 #include "base/memory/ref_counted_memory.h"
 #include "base/string_util.h"
 #include "base/stringprintf.h"
@@ skipping 14 matching lines @@
 const char kSearchIcon2xFilename[] = "images/2x/search_icon.png";
 
 }  // namespace
 
 LocalOmniboxPopupSource::LocalOmniboxPopupSource() {
 }
 
 LocalOmniboxPopupSource::~LocalOmniboxPopupSource() {
 }
 
-std::string LocalOmniboxPopupSource::GetSource() {
+std::string LocalOmniboxPopupSource::GetSource() const {
   return chrome::kChromeSearchLocalOmniboxPopupHost;
 }
 
 void LocalOmniboxPopupSource::StartDataRequest(
     const std::string& path,
     bool is_incognito,
     const content::URLDataSource::GotDataCallback& callback) {
   int identifier = -1;
   if (path == kHtmlFilename) {
     identifier = IDR_LOCAL_OMNIBOX_POPUP_HTML;
@@ skipping 47 matching lines @@
   }
   return false;
 }
 
 std::string LocalOmniboxPopupSource::GetContentSecurityPolicyFrameSrc() const {
   // Allow embedding of chrome search suggestion host.
   return base::StringPrintf("frame-src %s://%s/;",
                             chrome::kChromeSearchScheme,
                             chrome::kChromeSearchSuggestionHost);
 }