Add browser tests via karma

karma.conf.js

@@ -0,0 +1,54 @@
+module.exports = function(config) {
+    var configuration = {
+        frameworks: ["jasmine"],
+        files: [
+            {pattern: './ci/spec-bundle.js', watched: false}
+        ],
+        preprocessors: {
+            './ci/spec-bundle.js': ['webpack', 'sourcemap'],
+        },
+        webpackMiddleware: {
+            scripts: 'errors-only'
+        },
+        webpack: {
+            devtool: "inline-source-map",
+            resolve: {
+                extensions: ['.ts', '.js'],
+            },
+            module: {
+                rules: [
+                    {
+                        test: /\.ts$/,
+                        exclude: /node_modules/,
+                        use: [{loader: 'ts-loader', options: {transpileOnly: true}}]
+                    }
+                ]
+            },
+        },
+        mime: {
+            'text/x-typescript': ['ts', 'tsx']
+        },
+        reporters: ["progress"],
+        browsers: ["ChromeHeadless", "FirefoxHeadless"],
+        customLaunchers: {
+            ChromeHeadlessTravis: {
+                base: "ChromeHeadless",
+                flags: ['--no-sandbox']
+            }
+        },
+        concurrency: 8,
+        plugins: [
+            'karma-jasmine',
+            'karma-chrome-launcher',
+            'karma-firefox-launcher',
+            'karma-webpack',
+            'karma-sourcemap-loader'
+        ]
+    };
+
+    if (process.env.TRAVIS) {
+        configuration.browsers = ['ChromeHeadlessTravis', 'FirefoxHeadless'];
+    }
+
+    config.set(configuration);
+}