Make ExtensionIconSet::ContainsPath use StringPiece.

extensions/browser/extension_protocols.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 "extensions/browser/extension_protocols.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 375 matching lines @@
   return false;
 }
 
 // Returns true if the given URL references an icon in the given extension.
 bool URLIsForExtensionIcon(const GURL& url, const Extension* extension) {
   DCHECK(url.SchemeIs(extensions::kExtensionScheme));
 
   if (!extension)
     return false;
 
-  std::string path = url.path();
   DCHECK_EQ(url.host(), extension->id());
+  base::StringPiece path = url.path_piece();
   DCHECK(path.length() > 0 && path[0] == '/');
-  path = path.substr(1);
-  return extensions::IconsInfo::GetIcons(extension).ContainsPath(path);
+  base::StringPiece path_without_slash = path.substr(1);
+  return extensions::IconsInfo::GetIcons(extension).ContainsPath(
+      path_without_slash);
 }
 
 class ExtensionProtocolHandler
     : public net::URLRequestJobFactory::ProtocolHandler {
  public:
   ExtensionProtocolHandler(bool is_incognito,
                            extensions::InfoMap* extension_info_map)
       : is_incognito_(is_incognito), extension_info_map_(extension_info_map) {}
 
   ~ExtensionProtocolHandler() override {}
@@ skipping 186 matching lines @@
                                extensions::InfoMap* extension_info_map) {
   return base::MakeUnique<ExtensionProtocolHandler>(is_incognito,
                                                     extension_info_map);
 }
 
 void SetExtensionProtocolTestHandler(ExtensionProtocolTestHandler* handler) {
   g_test_handler = handler;
 }
 
 }  // namespace extensions