Merge pull request #7586 from samccone/sjs/fix_webpack_profiling_race

Fix race condition in profiling plugin.

lib/debug/ProfilingPlugin.js

@@ -130,7 +130,14 @@ function createTrace(outputPath) {
 		trace,
 		counter,
 		profiler,
-		end: callback => fsStream.end(callback)
+		end: callback => {
+			// Wait until the write stream finishes.
+			fsStream.on("finish", () => {
+				callback();
+			});
+			// Tear down the readable trace stream.
+			trace.destroy();
+		}
 	};
 }