Help gdb(1) find its way to the right thread.

It's more useful to attach to the crashing thread than the main thread.

Change-Id: Ibd8b67579e9e73101d9c56fc11dcead29ce7e7f5
diff --git a/src/runtime_linux.cc b/src/runtime_linux.cc
index a4bdacc..df66162 100644
--- a/src/runtime_linux.cc
+++ b/src/runtime_linux.cc
@@ -251,8 +251,8 @@
   // TODO: instead, get debuggerd running on the host, try to connect, and hang around on success.
   if (getenv("debug_db_uid") != NULL) {
     LOG(INTERNAL_FATAL) << "********************************************************\n"
-                        << "* Process " << getpid() << " has been suspended while crashing. Attach gdb:\n"
-                        << "*     gdb -p " << getpid() << "\n"
+                        << "* Process " << getpid() << " thread " << GetTid() << " has been suspended while crashing. Attach gdb:\n"
+                        << "*     gdb -p " << GetTid() << "\n"
                         << "********************************************************\n";
     // Wait for debugger to attach.
     while (true) {