Don't allow direct const char* trace value

Source/platform/ThreadTimers.cpp

Index: Source/platform/ThreadTimers.cpp
diff --git a/Source/platform/ThreadTimers.cpp b/Source/platform/ThreadTimers.cpp
index 43035709c8c1c4d16ea33166efc0f91a2ffb0d33..6b52c8267b32b0022ed8aabcecba90f8fb38ca91 100644
--- a/Source/platform/ThreadTimers.cpp
+++ b/Source/platform/ThreadTimers.cpp
@@ -131,8 +131,8 @@ void ThreadTimers::sharedTimerFiredInternal()
         timer.setNextFireTime(interval ? fireTime + interval : 0);
 
         TRACE_EVENT2("blink", "ThreadTimers::sharedTimerFiredInternal",
-            "src_file", timer.location().fileName(),
-            "src_func", timer.location().functionName());
+            "src_file", TRACE_STR_NO_COPY(timer.location().fileName()),
+            "src_func", TRACE_STR_NO_COPY(timer.location().functionName()));
 
         // Once the timer has been fired, it may be deleted, so do nothing else with it after this point.
         timer.fired();