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

net/test/url_request/url_request_mock_http_job.cc

Index: net/test/url_request/url_request_mock_http_job.cc
diff --git a/net/test/url_request/url_request_mock_http_job.cc b/net/test/url_request/url_request_mock_http_job.cc
index 5317b846ed0ce4f6d04f9e161e6d10e34e57f83c..ae1600215d6ebeb6d58b8e516bcb6411268f7cda 100644
--- a/net/test/url_request/url_request_mock_http_job.cc
+++ b/net/test/url_request/url_request_mock_http_job.cc
@@ -62,7 +62,7 @@ class MockJobInterceptor : public URLRequestInterceptor {
     // So first we convert base FilePath to a URL, then append the URL
     // path to that, and convert the final URL back to a FilePath.
     GURL file_url(FilePathToFileURL(base_path_));
-    std::string url = file_url.spec() + request->url().path();
+    std::string url = file_url.spec() + request->url().path().as_string();
     base::FilePath file_path;
     FileURLToFilePath(GURL(url), &file_path);
     return file_path;