title: webpack-dev-server & ts-loader not reloads when interface changed
body: <p>I'm using <code>webpack@4.16.1</code>, <code>webpack-dev-server@3.1.4</code> and <code>ts-loader@4.4.2</code>.</p>
  
  <p>I use <strong>Interface/index.ts</strong> to manage imports, to organize multiple interface imports.</p>
  
  <p>But When I change interface file, webpack-dev-server(or ts-loader, I don`t know) not reload &amp; transpile changed interface file.</p>
  
  <p><strong>Interface/IHelloState.ts</strong></p>
  
  <pre><code>export interface IHelloState {
      message: string;
  }
  </code></pre>
  
  <p><strong>Interface.index.ts</strong></p>
  
  <pre><code>export {IHelloState} from "./IHelloState";
  </code></pre>
  
  <p><strong>index.tsx</strong></p>
  
  <pre><code>import * as React from "react";
  import * as ReactDOM from "react-dom";
  import "./index.css";
  import {IHelloState} from "./Interface";
  
  const helloState: IHelloState = {
      message: "hello!"
  };
  
  ReactDOM.render(&lt;div&gt;{helloState.message}&lt;/div&gt;, document.getElementById("root"));
  </code></pre>
  
  <p>When I change <strong>Interface/IHelloState.ts</strong> like:</p>
  
  <p><strong>Interface/IHelloState.ts</strong></p>
  
  <pre><code>export interface IHelloState {
      // message: string;
  }
  </code></pre>
  
  <p>Nothing happens. Not even "[HMR] Checking for updates on the server..." or "[HMR] Nothing hot updated." shows.</p>
  
  <p>When I change <strong>Interface/IHelloState.ts</strong> and <strong>index.tsx</strong> like:</p>
  
  <p><strong>Interface/IHelloState.ts</strong></p>
  
  <pre><code>export interface IHelloState {
      message: string;
      state: boolean;
  }
  </code></pre>
  
  <p><strong>index.tsx</strong></p>
  
  <pre><code>import * as React from "react";
  import * as ReactDOM from "react-dom";
  import "./index.css";
  import {IHelloState} from "./Interface";
  
  const helloState: IHelloState = {
      message: "hello!",
      state: true
  };
  </code></pre>
  
  <p>Now and error reports.</p>
  
  <pre><code>[tsl] ERROR in (PATH...)\index.tsx(8,5)
        TS2322: Type '{ message: string; state: boolean; }' is not assignable to type 'IHelloState'.
    Object literal may only specify known properties, and 'state' does not exist in type 'IHelloState'.
  </code></pre>
  
  <p>What should I change?</p>
  
  <p>I run webpack-dev-server with <code>webpack-dev-server --config webpack.dev.config.js --hot</code>.</p>
  
  <p>This is my config file.</p>
  
  <p><strong>webpack.dev.config.js</strong></p>
  
  <pre><code>const path = require("path");
  const HtmlWebpackPlugin = require("html-webpack-plugin");
  const webpack = require("webpack");
  
  module.exports = Object.assign(require("./webpack.base.config"), {
      entry: [
          path.join(__dirname, "src/app/index.tsx"),
  
          "webpack/hot/only-dev-server"
      ],
  
      output: {
          path: path.join(__dirname, "build/app"),
          filename: "static/js/bundle.[hash].js"
      },
  
      module: {
          rules: [
              {
                  test: /\.jsx?$/,
                  loader: "babel-loader"
              }, {
                  test: /\.tsx?$/,
                  loader: "ts-loader",
                  options: {
                      configFile: "tsconfig.app.json"
                  }
              },
              {
                  test: /\.css$/,
                  use: [
                      "style-loader",
                      {
                          loader: "css-loader",
                          options: {
                              modules: false
                          }
                      }
                  ]
              },
              {
                  exclude: [/\.tsx?/, /\.jsx?$/, /\.html$/, /\.css$/, /\.json$/],
                  loader: "file-loader",
                  options: {
                      name: "static/files/[hash].[ext]"
                  }
              }
          ]
      },
  
      resolve: {
          extensions: [".ts", ".tsx", ".js", ".jsx", ".css", ".json"]
      },
  
      plugins: [
          new HtmlWebpackPlugin({
              template: path.join(__dirname, "src/app/index.html")
          }),
  
          new webpack.HotModuleReplacementPlugin()
      ],
  
      devServer: {
          historyApiFallback: {
              index: "/"
          }
      },
  
      target: "electron-renderer",
  
      mode: "development"
  });
  </code></pre>