Auto merge of #11534 - izgzhen:add-blob-url-store, r=Manishearth

Add Blob URL store

Spec: https://w3c.github.io/FileAPI/#BlobURLStore.

I finally decide to put the store under `ScriptThread` and interpret the "global object" as the script thread itself. The new APIs will be used during the page loading (if scheme is `blob`) and `URL.createObjectURL/revokeObjectURL`.

Related to #11131.

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- [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

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- [x] These changes do not require tests because it is new stub code which needs further integrating PRs.

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components/script/dom/window.rs

@@ -3,6 +3,7 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 use app_units::Au;
+use blob_url_store::BlobURLStore;
 use devtools_traits::{ScriptToDevtoolsControlMsg, TimelineMarker, TimelineMarkerType, WorkerId};
 use dom::bindings::callback::ExceptionHandling;
 use dom::bindings::cell::DOMRefCell;
@@ -165,6 +166,9 @@ pub struct Window {
     scheduler_chan: IpcSender<TimerEventRequest>,
     timers: OneshotTimers,
 
+    /// Blob URL store
+    blob_url_store: DOMRefCell<BlobURLStore>,
+
     next_worker_id: Cell<WorkerId>,
 
     /// For sending messages to the memory profiler.
@@ -1581,6 +1585,7 @@ impl Window {
             console: Default::default(),
             crypto: Default::default(),
             navigator: Default::default(),
+            blob_url_store: DOMRefCell::new(BlobURLStore::new()),
             image_cache_thread: image_cache_thread,
             mem_profiler_chan: mem_profiler_chan,
             time_profiler_chan: time_profiler_chan,

components/script/dom/workerglobalscope.rs

@@ -2,7 +2,9 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+use blob_url_store::BlobURLStore;
 use devtools_traits::{DevtoolScriptControlMsg, ScriptToDevtoolsControlMsg, WorkerId, DevtoolsPageInfo};
+use dom::bindings::cell::DOMRefCell;
 use dom::bindings::codegen::Bindings::FunctionBinding::Function;
 use dom::bindings::codegen::Bindings::WorkerGlobalScopeBinding::WorkerGlobalScopeMethods;
 use dom::bindings::error::{Error, ErrorResult, Fallible, report_pending_exception};
@@ -113,6 +115,9 @@ pub struct WorkerGlobalScope {
     console: MutNullableHeap<JS<Console>>,
     crypto: MutNullableHeap<JS<Crypto>>,
     timers: OneshotTimers,
+    /// Blob URL store
+    blob_url_store: DOMRefCell<BlobURLStore>,
+
     #[ignore_heap_size_of = "Defined in std"]
     mem_profiler_chan: mem::ProfilerChan,
     #[ignore_heap_size_of = "Defined in std"]
@@ -172,6 +177,7 @@ impl WorkerGlobalScope {
             console: Default::default(),
             crypto: Default::default(),
             timers: OneshotTimers::new(timer_event_chan, init.scheduler_chan.clone()),
+            blob_url_store: DOMRefCell::new(BlobURLStore::new()),
             mem_profiler_chan: init.mem_profiler_chan,
             time_profiler_chan: init.time_profiler_chan,
             to_devtools_sender: init.to_devtools_sender,