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

This patch was generated by running the empty_string clang tool
across the Chromium Linux compilation database. Implicitly or
explicitly constructing std::string() with a "" argument is
inefficient as the caller needs to emit extra instructions to
pass an argument, and the constructor needlessly copies a byte
into internal storage. Rewriting these instances to simply call
the default constructor appears to save ~14-18 kilobytes on an
optimized release build.

BUG=none

Review URL: https://codereview.chromium.org/13145003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@193020 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 3 insertions, 2 deletions

diff --git a/remoting/protocol/jingle_session.cc b/remoting/protocol/jingle_session.cc
index c6a4f22..72985c2 100644
--- a/remoting/protocol/jingle_session.cc
+++ b/remoting/protocol/jingle_session.cc
@@ -323,7 +323,8 @@ void JingleSession::OnMessageResponse(
     CloseInternal(SIGNALING_TIMEOUT);
     return;
   } else {
-    const std::string& type = response->Attr(buzz::QName("", "type"));
+    const std::string& type =
+        response->Attr(buzz::QName(std::string(), "type"));
     if (type != "result") {
       LOG(ERROR) << "Received error in response to " << type_str
                  << " message: \"" << response->Str()
@@ -383,7 +384,7 @@ void JingleSession::OnTransportInfoResponse(IqRequest* request,
     return;
   }
 
-  const std::string& type = response->Attr(buzz::QName("", "type"));
+  const std::string& type = response->Attr(buzz::QName(std::string(), "type"));
   if (type != "result") {
     LOG(ERROR) << "Received error in response to transport-info message: \""
                << response->Str() << "\". Terminating the session.";