switch some classes to class propertie initialisers

packages/babel/src/transformation/file/index.js

@@ -26,18 +26,25 @@ import * as t from "../../types";
 
 export default class File {
   constructor(opts = {}, pipeline) {
-    this.transformerDependencies = {};
+    this.pipeline = pipeline;
 
-    this.dynamicImportTypes = {};
-    this.dynamicImportIds   = {};
-    this.dynamicImports     = [];
+    this.log  = new Logger(this, opts.filename || "unknown");
+    this.opts = this.initOptions(opts);
 
-    this.declarations = {};
-    this.usedHelpers  = {};
-    this.dynamicData  = {};
-    this.data         = {};
+    this.buildTransformers();
+  }
 
-    this.metadata = {
+  transformerDependencies = {};
+  dynamicImportTypes      = {};
+  dynamicImportIds        = {};
+  dynamicImports          = [];
+  declarations            = {};
+  usedHelpers             = {};
+  dynamicData             = {};
+  data                    = {};
+  ast                     = {};
+
+  metadata = {
     modules: {
       imports: [],
       exports: {
@@ -47,15 +54,7 @@ export default class File {
     }
   };
 
-    this.pipeline = pipeline;
-    this.log      = new Logger(this, opts.filename || "unknown");
-    this.opts     = this.initOptions(opts);
-    this.ast      = {};
-
-    this.buildTransformers();
-
-    this.hub = new Hub(this);
-  }
+  hub = new Hub(this);
 
   /**
    * [Please add a description.]

packages/babel/src/transformation/pipeline.js

@@ -10,13 +10,11 @@ import File from "./file";
  */
 
 export default class Pipeline {
-  constructor() {
-    this.transformers = object();
-    this.namespaces   = object();
-    this.deprecated   = object();
-    this.aliases      = object();
-    this.filters      = [];
-  }
+  transformers = object();
+  namespaces   = object();
+  deprecated   = object();
+  aliases      = object();
+  filters      = [];
 
   /**
    * [Please add a description.]