service worker: Wait for request body blobs to finish construction

third_party/WebKit/LayoutTests/http/tests/serviceworker/resources/request-body-blob-worker.js

+self.addEventListener('fetch', event => {
+    if (event.request.url.indexOf('?post-with-blob-body') == -1)
+      return;
+    event.respondWith(
+     event.request.text().then(resp => {
+       if (resp.indexOf("it's me the blob") == -1)

[horo, 2016/05/12 06:13:36]

Nit: use single quotes

[falken, 2016/05/12 08:49:33]

Done.

+         return new Response('fail');
+       if (resp.indexOf("and more blob!") == -1)

[horo, 2016/05/12 06:13:36]

Nit: use single quotes

[falken, 2016/05/12 08:49:33]

Done.

+         return new Response('fail');
+       return new Response('Pass');
+     }));
+  });