pkg/compiler: fix imports

pkg/compiler/lib/src/cps_ir/loop_effects.dart

 library dart2js.cps_ir.loop_effects;
 
+import '../world.dart';
 import 'cps_ir_nodes.dart';
+import 'effects.dart';
 import 'loop_hierarchy.dart';
-import '../world.dart';
-import 'effects.dart';
 
 /// Determines the side effects that may occur in each loop.
 class LoopSideEffects extends TrampolineRecursiveVisitor {
   LoopHierarchy loopHierarchy;
   final World world;
   final Map<Continuation, List<Continuation>> exitContinuations = {};
   final Map<Continuation, int> loopSideEffects = {};
   Continuation currentLoopHeader;
 
   LoopSideEffects(FunctionDefinition node, this.world, {this.loopHierarchy}) {
@@ skipping 73 matching lines @@
               'Unreachable continuations must be removed before computing '
               'loop side effects.');
         }
         inner = outer;
         outer = loopHierarchy.getEnclosingLoop(outer);
       }
       exitContinuations[inner].add(cont);
     }
   }
 }