Include the thread name in Thread's operator<< output.

For example:

 Thread[2,tid=1692,VmWait,Thread*=0x416914d0,"Signal Catcher"]: reacting to signal 3

Change-Id: I2b00e82af2ad0f09141dbf4e418bc0582e9b966d
diff --git a/src/trace.cc b/src/trace.cc
index c149634..83f50d3 100644
--- a/src/trace.cc
+++ b/src/trace.cc
@@ -402,7 +402,7 @@
 
 static void DumpThread(Thread* t, void* arg) {
   std::ostream* os = reinterpret_cast<std::ostream*>(arg);
-  *os << StringPrintf("%d\t%s\n", t->GetTid(), t->GetName()->ToModifiedUtf8().c_str());
+  *os << StringPrintf("%d\t%s\n", t->GetTid(), t->GetThreadName()->ToModifiedUtf8().c_str());
 }
 
 void Trace::DumpThreadList(std::ostream& os) {