Rewrite std::string("") to std::string(), Linux edition.

net/http/http_stream_factory_impl_unittest.cc

Index: net/http/http_stream_factory_impl_unittest.cc
diff --git a/net/http/http_stream_factory_impl_unittest.cc b/net/http/http_stream_factory_impl_unittest.cc
index 0a9437f7c02ee4985b86178df2eff03f4eccf3a2..f228d9afdbf960b33d70df5935a2d7700b4c5ec1 100644
--- a/net/http/http_stream_factory_impl_unittest.cc
+++ b/net/http/http_stream_factory_impl_unittest.cc
@@ -271,11 +271,24 @@ CapturePreconnectsHttpProxySocketPool::CapturePreconnectsSocketPool(
     : HttpProxyClientSocketPool(0, 0, NULL, host_resolver, NULL, NULL, NULL),
       last_num_streams_(-1) {}
 
-template<>
+template <>
 CapturePreconnectsSSLSocketPool::CapturePreconnectsSocketPool(
-    HostResolver* host_resolver, CertVerifier* cert_verifier)
-    : SSLClientSocketPool(0, 0, NULL, host_resolver, cert_verifier, NULL,
-                          NULL, "", NULL, NULL, NULL, NULL, NULL, NULL),
+    HostResolver* host_resolver,
+    CertVerifier* cert_verifier)
+    : SSLClientSocketPool(0,
+                          0,
+                          NULL,
+                          host_resolver,
+                          cert_verifier,
+                          NULL,
+                          NULL,
+                          std::string(),
+                          NULL,
+                          NULL,
+                          NULL,
+                          NULL,
+                          NULL,
+                          NULL),
       last_num_streams_(-1) {}
 
 TEST(HttpStreamFactoryTest, PreconnectDirect) {