Teach i18nTemplate.process() to handle <link rel=import> and <template>

ui/webui/resources/js/webui_resource_test.js

Index: ui/webui/resources/js/webui_resource_test.js
diff --git a/ui/webui/resources/js/webui_resource_test.js b/ui/webui/resources/js/webui_resource_test.js
index a1a542eb4490b695302188418f1be2e3f6d16b18..2b1660a85d9349b66f89fd1052efbd8da30bc817 100644
--- a/ui/webui/resources/js/webui_resource_test.js
+++ b/ui/webui/resources/js/webui_resource_test.js
@@ -150,6 +150,12 @@ function assertDeepEquals(expected, observed, opt_message) {
       console.error('Failed to find test cases.');
       cleanTestRun = false;
     }
+    try {
+      if (window.setUpPage)
+        window.setUpPage();
+    } catch(err) {
+      cleanTestRun = false;
+    }
     continueTesting();
   }