fix(config): revert esmLoaderPath change (#1561)

Author: manucorporat

BREAKING_CHANGES.md

@@ -137,16 +137,6 @@ import { JSX } from '@stencil/core';
 export type StencilIntrinsicElement = JSX.IntrinsicElement;
 ```
 
-### Moved loader entrypoint
-
-Now the `loader` entrypoint, useful to register the web components in webpack projects, has been moved outside the `dist` folder.
-By default `loader` will be a sibling of `dist` now:
-
-```diff
-- import { defineCustomElements } from 'my-collection/dist/loader';
-+ import { defineCustomElements } from 'my-collection/loader';
-```
-
 ### Removed: @Listen('event.KEY’)
 
 It's no longer possible to use the `event.KEY` syntax in the `@Listen` decorator in order to only listen for specific key strokes.

src/compiler/config/validate-outputs-dist.ts

@@ -43,7 +43,7 @@ export function validateOutputTargetDist(config: d.Config) {
     }
 
     if (!path.isAbsolute(outputTarget.esmLoaderPath)) {
-      outputTarget.esmLoaderPath = normalizePath(path.resolve(config.rootDir, outputTarget.esmLoaderPath));
+      outputTarget.esmLoaderPath = normalizePath(path.resolve(outputTarget.dir, outputTarget.esmLoaderPath));
     }
 
     if (!outputTarget.typesDir) {

src/compiler/output-targets/test/output-targets-dist.spec.ts

@@ -64,7 +64,7 @@ describe('outputTarget, dist', () => {
       path.join(root, 'User', 'testing', 'dist', 'esm', 'legacy', 'loader.mjs'),
       path.join(root, 'User', 'testing', 'dist', 'esm', 'polyfills', 'index.js'),
 
-      path.join(root, 'User', 'testing',  'loader'),
+      path.join(root, 'User', 'testing', 'dist', 'loader'),
 
       path.join(root, 'User', 'testing', 'dist', 'types'),
 

test/karma/test-app/esm-webpack/index.esm.js

@@ -1,3 +1,3 @@
-import { defineCustomElements } from '../../loader';
+import { defineCustomElements } from '../../test-dist/loader';
 
 defineCustomElements(window);