[WIP] make GURL::path() return a StringPiece

components/test_runner/mock_web_document_subresource_filter.cc

Index: components/test_runner/mock_web_document_subresource_filter.cc
diff --git a/components/test_runner/mock_web_document_subresource_filter.cc b/components/test_runner/mock_web_document_subresource_filter.cc
index bdd1e53a04d6655b5e244380f65611b6b6685de5..f9f0cb2386e4c9881c6bdcccd8f8764783ab3b47 100644
--- a/components/test_runner/mock_web_document_subresource_filter.cc
+++ b/components/test_runner/mock_web_document_subresource_filter.cc
@@ -21,7 +21,7 @@ MockWebDocumentSubresourceFilter::~MockWebDocumentSubresourceFilter() {}
 bool MockWebDocumentSubresourceFilter::allowLoad(
     const blink::WebURL& resource_url,
     blink::WebURLRequest::RequestContext /* ignored */) {
-  const std::string resource_path(GURL(resource_url).path());
+  const base::StringPiece resource_path(GURL(resource_url).path());
   return std::find_if(disallowed_path_suffixes_.begin(),
                       disallowed_path_suffixes_.end(),
                       [&resource_path](const std::string& suffix) {