Added support to trace_event for passing static string arguments without copy

base/debug/trace_event.cc

Index: base/debug/trace_event.cc
diff --git a/base/debug/trace_event.cc b/base/debug/trace_event.cc
index c983df9a4468e416f6a331aa634906db9d6fd0ca..81f6d7cd84b2df7bfbed8382d3f1c67c3ac1b457 100644
--- a/base/debug/trace_event.cc
+++ b/base/debug/trace_event.cc
@@ -83,6 +83,7 @@ void TraceValue::AppendAsJSON(std::string* out) const {
       *out += temp_string;
       break;
     case TRACE_TYPE_STRING:
+    case TRACE_TYPE_STATIC_STRING:
       *out += "\"";
       start_pos = out->size();
       *out += as_string();