flush the chrome trace file before adding the eof metadata

Author: bashbaug

intercept/src/chrometracer.h

@@ -27,14 +27,15 @@ class CChromeTracer
 
     ~CChromeTracer()
     {
+        flush();
+
         // Add an eof metadata event without a trailing comma to properly end
         // the json file.
         m_TraceFile
             << "{\"ph\":\"M\",\"name\":\"clintercept_eof\",\"pid\":" << m_ProcessId
             << ",\"tid\":0"
             << "}\n"
             << "]\n";
-        flush();
         m_TraceFile.close();
     }