Auto merge of #11716 - izgzhen:impl-blob-url-dom, r=Manishearth

Implement Blob URL's DOM interfaces

r? @Manishearth

Implement the two functions in `URL` to create/revoke Blob URLs, and related code to approximate our proposed design to make things work together.

<!-- Please describe your changes on the following line: -->

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix part of #10539, related to #11131

<!-- Either: -->
- [x] There are tests for these changes OR

<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->

<!-- Reviewable:start -->
---
This change is [<img src="https://reviewable.io/review_button.svg" height="35" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/servo/11716)
<!-- Reviewable:end -->

1 files changed, 4 insertions, 1 deletions

diff --git a/components/script/dom/worker.rs b/components/script/dom/worker.rs
index 5762e2aa63f..a136f4ec8ca 100644
--- a/components/script/dom/worker.rs
+++ b/components/script/dom/worker.rs
@@ -147,7 +147,10 @@ impl WorkerMethods for Worker {
     fn PostMessage(&self, cx: *mut JSContext, message: HandleValue) -> ErrorResult {
         let data = try!(StructuredCloneData::write(cx, message));
         let address = Trusted::new(self);
-        self.sender.send((address, WorkerScriptMsg::DOMMessage(data))).unwrap();
+
+        // NOTE: step 9 of https://html.spec.whatwg.org/multipage/#dom-messageport-postmessage
+        // indicates that a nonexistent communication channel should result in a silent error.
+        let _ = self.sender.send((address, WorkerScriptMsg::DOMMessage(data)));
         Ok(())
     }