run actions only in the right state

benchmarking/src/benchmarks/BenchmarkSuite.js

@@ -56,17 +56,25 @@ export class BenchmarkSuite {
   }
 
   start() {
-    this.state = 'running'
-    this.run()
+    if (this.state === 'initialized' || this.state === 'paused') {
+      this.state = 'running'
+      this.run()
+    }
   }
 
   pause() {
-    this.state = 'pause_requested'
+    if (this.state === 'running') this.state = 'pause_requested'
   }
 
   stop() {
-    this.state = 'stop_requested'
-    this.run()
+    if (
+      this.state === 'running' ||
+      this.state === 'paused' ||
+      this.state === 'finished'
+    ) {
+      this.state = 'stop_requested'
+      this.run()
+    }
   }
 }