wip: address review comments

and run performance

packages/@lwc/engine/src/framework/base-lightning-element.ts

@@ -35,7 +35,7 @@ import {
 import { ViewModelReflection, EmptyObject } from './utils';
 import { vmBeingConstructed, isBeingConstructed, isRendering, vmBeingRendered } from './invoker';
 import { getComponentVM, VM } from './vm';
-import { valueMutated, valueObserved } from './mutation-tracker';
+import { componentValueMutated, valueObserved } from './mutation-tracker';
 import { dispatchEvent } from '../env/dom';
 import { patchComponentWithRestrictions, patchShadowRootWithRestrictions } from './restrictions';
 import { unlockAttribute, lockAttribute } from './attributes';
@@ -116,7 +116,7 @@ function createBridgeToElementDescriptor(
             if (newValue !== vm.cmpProps[propName]) {
                 vm.cmpProps[propName] = newValue;
 
-                valueMutated(vm, propName);
+                componentValueMutated(vm, propName);
             }
             return set.call(vm.elm, newValue);
         },

packages/@lwc/engine/src/framework/decorators/api.ts

@@ -7,7 +7,7 @@
 import { assert, isFunction, toString } from '@lwc/shared';
 import { logError } from '../../shared/assert';
 import { isRendering, vmBeingRendered, isBeingConstructed } from '../invoker';
-import { valueObserved, valueMutated } from '../mutation-tracker';
+import { valueObserved, componentValueMutated } from '../mutation-tracker';
 import { ComponentInterface } from '../component';
 import { getComponentVM } from '../vm';
 
@@ -59,7 +59,7 @@ export function createPublicPropertyDescriptor(key: string): PropertyDescriptor
             }
             vm.cmpProps[key] = newValue;
 
-            valueMutated(vm, key);
+            componentValueMutated(vm, key);
         },
         enumerable: true,
         configurable: true,

packages/@lwc/engine/src/framework/decorators/track.ts

@@ -6,7 +6,7 @@
  */
 import { assert } from '@lwc/shared';
 import { isRendering, vmBeingRendered } from '../invoker';
-import { valueObserved, valueMutated } from '../mutation-tracker';
+import { valueObserved, componentValueMutated } from '../mutation-tracker';
 import { getComponentVM } from '../vm';
 import { reactiveMembrane } from '../membrane';
 import { ComponentInterface } from '../component';
@@ -54,7 +54,7 @@ export function internalTrackDecorator(key: string): PropertyDescriptor {
             if (reactiveOrAnyValue !== vm.cmpFields[key]) {
                 vm.cmpFields[key] = reactiveOrAnyValue;
 
-                valueMutated(vm, key);
+                componentValueMutated(vm, key);
             }
         },
         enumerable: true,

packages/@lwc/engine/src/framework/membrane.ts

@@ -5,7 +5,7 @@
  * For full license text, see the LICENSE file in the repo root or https://opensource.org/licenses/MIT
  */
 import ObservableMembrane from 'observable-membrane';
-import { valueObserved, valueMutated } from '../libs/mutation-tracker';
+import { valueObserved, valueMutated } from './mutation-tracker';
 
 function valueDistortion(value: any) {
     return value;

packages/@lwc/engine/src/framework/mutation-tracker.ts

@@ -1,16 +1,18 @@
-import {
-    valueMutated as mtValueMutated,
-    valueObserved,
-    ReactiveObserver,
-} from '../libs/mutation-tracker';
+/*
+ * Copyright (c) 2018, salesforce.com, inc.
+ * All rights reserved.
+ * SPDX-License-Identifier: MIT
+ * For full license text, see the LICENSE file in the repo root or https://opensource.org/licenses/MIT
+ */
+import { valueMutated } from '../libs/mutation-tracker';
 import { VM } from './vm';
 // import { isFalse } from "@lwc/shared";
 
-export function valueMutated(vm: VM, key: PropertyKey) {
+export function componentValueMutated(vm: VM, key: PropertyKey) {
     const { component } = vm;
     // if (isFalse(vm.isDirty)) {
-    mtValueMutated(component, key);
+    valueMutated(component, key);
     // }
 }
 
-export { valueObserved, ReactiveObserver };
+export * from '../libs/mutation-tracker';

packages/@lwc/engine/src/framework/observed-fields.ts

@@ -7,7 +7,7 @@
 import { assert } from '@lwc/shared';
 import { ComponentInterface } from './component';
 import { getComponentVM } from './vm';
-import { valueMutated, valueObserved } from './mutation-tracker';
+import { componentValueMutated, valueObserved } from './mutation-tracker';
 
 export function createObservedFieldPropertyDescriptor(key: string): PropertyDescriptor {
     return {
@@ -28,7 +28,7 @@ export function createObservedFieldPropertyDescriptor(key: string): PropertyDesc
             if (newValue !== vm.cmpFields[key]) {
                 vm.cmpFields[key] = newValue;
 
-                valueMutated(vm, key);
+                componentValueMutated(vm, key);
             }
         },
         enumerable: true,

packages/@lwc/engine/src/framework/wiring.ts

@@ -6,7 +6,7 @@
  */
 import { assert, isUndefined, ArrayPush, getOwnPropertyNames } from '@lwc/shared';
 import { ComponentInterface } from './component';
-import { valueMutated, ReactiveObserver } from './mutation-tracker';
+import { componentValueMutated, ReactiveObserver } from './mutation-tracker';
 import { VM, runWithBoundaryProtection } from './vm';
 import { invokeComponentCallback } from './invoker';
 import { dispatchEvent } from '../env/dom';
@@ -21,7 +21,7 @@ function createFieldDataCallback(vm: VM, name: string) {
             // storing the value in the underlying storage
             cmpFields[name] = value;
 
-            valueMutated(vm, name);
+            componentValueMutated(vm, name);
         }
     };
 }