ssr-tests: add better error messsages

Previously the error object was used to generate a new error object which
had the effect of removing the stack trace from the actual error. This
made debugging SSR test failures very difficult. Now we just propagate
the original error.

apps/ssr-tests/test/test.js

@@ -46,6 +46,12 @@ describe('Utilities', () => {
       assert.equal(library.getDocument(), undefined);
     });
   });
+
+  describe('canUseDOM', () => {
+    it('returns false in server environment', () => {
+      assert.equal(library.canUseDOM(), false);
+    });
+  });
 });
 
 function testRender(componentName, component) {
@@ -56,7 +62,7 @@ function testRender(componentName, component) {
       ReactDOMServer.renderToString(elem);
       done();
     } catch (e) {
-      done(new Error(e));
+      done(e);
     }
   });
 }