minor #485 Fix small mistakes in shared-entry-concat-plugin.js and validator.js (Lyrkan)

This PR was merged into the master branch.

Discussion
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Fix small mistakes in shared-entry-concat-plugin.js and validator.js

Just two small issues I noticed while playing with the TypeScript compiler :)

Commits
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828788c Fix some issues in shared-entry-concat-plugin.js and validator.js

Author: weaverryan

lib/config/validator.js

@@ -79,5 +79,5 @@ class Validator {
 module.exports = function(webpackConfig) {
     const validator = new Validator(webpackConfig);
 
-    validator.validate(webpackConfig);
+    validator.validate();
 };

lib/webpack/shared-entry-concat-plugin.js

@@ -41,7 +41,7 @@ function getChunkFilename(compilation, chunkName) {
 function getAssetSource(asset) {
     let content = asset.source();
     if (Buffer.isBuffer(content)) {
-        content = Buffer.toString('utf-8');
+        content = content.toString('utf-8');
     }
 
     return content;