Turn test runner library into an actual component

content/shell/renderer/layout_test/blink_test_runner.cc

Index: content/shell/renderer/layout_test/blink_test_runner.cc
diff --git a/content/shell/renderer/layout_test/blink_test_runner.cc b/content/shell/renderer/layout_test/blink_test_runner.cc
index b17da212d91dc743367e3414b47a90509309c499..5372c60b10df4d602e156274a8eb521697d6ac03 100644
--- a/content/shell/renderer/layout_test/blink_test_runner.cc
+++ b/content/shell/renderer/layout_test/blink_test_runner.cc
@@ -681,8 +681,7 @@ void BlinkTestRunner::ResolveBeforeInstallPromptPromise(
       int request_id, const std::string& platform) {
   test_runner::WebTestInterfaces* interfaces =
       LayoutTestRenderProcessObserver::GetInstance()->test_interfaces();
-  interfaces->GetTestInterfaces()->GetAppBannerClient()->ResolvePromise(
-      request_id, platform);
+  interfaces->GetAppBannerClient()->ResolvePromise(request_id, platform);
 }
 
 blink::WebPlugin* BlinkTestRunner::CreatePluginPlaceholder(