refactor(MapWrapper): drop delete(), get(), forEach() and size

Closes #4618

modules/angular2/src/core/change_detection/codegen_name_util.ts

@@ -83,7 +83,7 @@ export class CodegenNameUtil {
   getLocalName(idx: number): string { return `l_${this._sanitizedNames[idx]}`; }
 
   getEventLocalName(eb: EventBinding, idx: number): string {
-    return `l_${MapWrapper.get(this._sanitizedEventNames, eb)[idx]}`;
+    return `l_${this._sanitizedEventNames.get(eb)[idx]}`;
   }
 
   getChangeName(idx: number): string { return `c_${this._sanitizedNames[idx]}`; }
@@ -118,7 +118,7 @@ export class CodegenNameUtil {
    */
   genInitEventLocals(): string {
     var res = [`${this.getLocalName(CONTEXT_INDEX)} = ${this.getFieldName(CONTEXT_INDEX)}`];
-    MapWrapper.forEach(this._sanitizedEventNames, (names, eb) => {
+    this._sanitizedEventNames.forEach((names, eb) => {
       for (var i = 0; i < names.length; ++i) {
         if (i !== CONTEXT_INDEX) {
           res.push(`${this.getEventLocalName(eb, i)}`);

modules/angular2/src/core/change_detection/differs/default_iterable_differ.ts

@@ -608,12 +608,12 @@ class _DuplicateMap {
     var recordList: _DuplicateItemRecordList = this.map.get(key);
     // Remove the list of duplicates when it gets empty
     if (recordList.remove(record)) {
-      MapWrapper.delete(this.map, key);
+      this.map.delete(key);
     }
     return record;
   }
 
-  get isEmpty(): boolean { return MapWrapper.size(this.map) === 0; }
+  get isEmpty(): boolean { return this.map.size === 0; }
 
   clear() { this.map.clear(); }
 

modules/angular2/src/core/change_detection/differs/default_keyvalue_differ.ts

@@ -1,4 +1,4 @@
-import {ListWrapper, MapWrapper, StringMapWrapper} from 'angular2/src/core/facade/collection';
+import {MapWrapper, StringMapWrapper} from 'angular2/src/core/facade/collection';
 import {stringify, looseIdentical, isJsObject, CONST, isBlank} from 'angular2/src/core/facade/lang';
 import {BaseException} from 'angular2/src/core/facade/exceptions';
 import {ChangeDetectorRef} from '../change_detector_ref';
@@ -197,7 +197,7 @@ export class DefaultKeyValueDiffer implements KeyValueDiffer {
     for (var rec: KVChangeRecord = this._removalsHead; rec !== null; rec = rec._nextRemoved) {
       rec.previousValue = rec.currentValue;
       rec.currentValue = null;
-      MapWrapper.delete(this._records, rec.key);
+      this._records.delete(rec.key);
     }
   }
 
@@ -317,7 +317,7 @@ export class DefaultKeyValueDiffer implements KeyValueDiffer {
 
   _forEach(obj, fn: Function) {
     if (obj instanceof Map) {
-      MapWrapper.forEach(obj, fn);
+      (<Map<any, any>>obj).forEach(<any>fn);
     } else {
       StringMapWrapper.forEach(obj, fn);
     }