Migrate PushMessagingBridge to use GC mojo wrappers.

No behavior change. This CL reduces potential risks of use-after-free bugs.

Bug: 1049056
Change-Id: Ibc8df682db4772ceedd4ddffbf781058bb7e6465
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2134098Reviewed-by: Kentaro Hara <haraken@chromium.org>
Commit-Queue: Minoru Chikamune <chikamune@chromium.org>
Cr-Commit-Position: refs/heads/master@{#756614}

third_party/blink/renderer/modules/push_messaging/push_messaging_bridge.cc

@@ -41,7 +41,8 @@ PushMessagingBridge* PushMessagingBridge::From(
 
 PushMessagingBridge::PushMessagingBridge(
     ServiceWorkerRegistration& registration)
-    : Supplement<ServiceWorkerRegistration>(registration) {}
+    : Supplement<ServiceWorkerRegistration>(registration),
+      permission_service_(nullptr) {}
 
 PushMessagingBridge::~PushMessagingBridge() = default;
 
@@ -51,9 +52,10 @@ ScriptPromise PushMessagingBridge::GetPermissionState(
     ScriptState* script_state,
     const PushSubscriptionOptionsInit* options) {
   ExecutionContext* context = ExecutionContext::From(script_state);
-  if (!permission_service_) {
+  if (!permission_service_.is_bound()) {
     ConnectToPermissionService(
-        context, permission_service_.BindNewPipeAndPassReceiver());
+        context, permission_service_.BindNewPipeAndPassReceiver(
+                     context->GetTaskRunner(TaskType::kMiscPlatformAPI)));
   }
 
   auto* resolver = MakeGarbageCollected<ScriptPromiseResolver>(script_state);
@@ -78,6 +80,11 @@ ScriptPromise PushMessagingBridge::GetPermissionState(
   return promise;
 }
 
+void PushMessagingBridge::Trace(Visitor* visitor) {
+  visitor->Trace(permission_service_);
+  Supplement<ServiceWorkerRegistration>::Trace(visitor);
+}
+
 void PushMessagingBridge::DidGetPermissionState(
     ScriptPromiseResolver* resolver,
     mojom::blink::PermissionStatus status) {

third_party/blink/renderer/modules/push_messaging/push_messaging_bridge.h

@@ -6,11 +6,12 @@
 #define THIRD_PARTY_BLINK_RENDERER_MODULES_PUSH_MESSAGING_PUSH_MESSAGING_BRIDGE_H_
 
 #include "base/macros.h"
-#include "mojo/public/cpp/bindings/remote.h"
 #include "third_party/blink/public/mojom/permissions/permission.mojom-blink.h"
 #include "third_party/blink/public/mojom/permissions/permission_status.mojom-blink.h"
 #include "third_party/blink/renderer/modules/service_worker/service_worker_registration.h"
 #include "third_party/blink/renderer/platform/heap/garbage_collected.h"
+#include "third_party/blink/renderer/platform/mojo/heap_mojo_remote.h"
+#include "third_party/blink/renderer/platform/mojo/heap_mojo_wrapper_mode.h"
 #include "third_party/blink/renderer/platform/supplementable.h"
 
 namespace blink {
@@ -40,13 +41,17 @@ class PushMessagingBridge final : public GarbageCollected<PushMessagingBridge>,
   ScriptPromise GetPermissionState(ScriptState* script_state,
                                    const PushSubscriptionOptionsInit* options);
 
+  void Trace(Visitor*) override;
+
  private:
   // Method to be invoked when the permission status has been retrieved from the
   // permission service. Will settle the given |resolver|.
   void DidGetPermissionState(ScriptPromiseResolver* resolver,
                              mojom::blink::PermissionStatus status);
 
-  mojo::Remote<mojom::blink::PermissionService> permission_service_;
+  HeapMojoRemote<mojom::blink::PermissionService,
+                 HeapMojoWrapperMode::kWithoutContextObserver>
+      permission_service_;
 
   DISALLOW_COPY_AND_ASSIGN(PushMessagingBridge);
 };