test: update karma runner (#2524)

* test: update karma runner

* fix: Promise polyfill for testrunner

tests/types.ts

@@ -0,0 +1,13 @@
+export interface PlatformDetails {
+    name: string;
+    version: string;
+}
+
+export interface ScreenshotRequest {
+    screenshot: string;
+    test: string;
+    platform: PlatformDetails;
+    devicePixelRatio: number;
+    windowWidth: number;
+    windowHeight: number;
+}