Code simplification: Don't store the same information in two places

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=179108920

src/com/google/javascript/jscomp/PhaseOptimizer.java

@@ -150,22 +150,19 @@ PhaseOptimizer withProgress(ProgressRange range) {
    */
   void consume(List<PassFactory> factories) {
     Loop currentLoop = new Loop();
-    boolean isCurrentLoopPopulated = false;
     for (PassFactory factory : factories) {
       if (factory.isOneTimePass()) {
-        if (isCurrentLoopPopulated) {
+        if (currentLoop.isPopulated()) {
           passes.add(currentLoop);
           currentLoop = new Loop();
-          isCurrentLoopPopulated = false;
         }
         addOneTimePass(factory);
       } else {
         currentLoop.addLoopedPass(factory);
-        isCurrentLoopPopulated = true;
       }
     }
 
-    if (isCurrentLoopPopulated) {
+    if (currentLoop.isPopulated()) {
       passes.add(currentLoop);
     }
   }
@@ -536,6 +533,10 @@ private void optimizePasses() {
       myPasses.addAll(optimalPasses);
     }
 
+    boolean isPopulated() {
+      return !myPasses.isEmpty();
+    }
+
     private boolean isCodeRemovalLoop() {
       for (NamedPass pass : this.myPasses) {
         if (CODE_REMOVING_PASSES.contains(pass.name)) {