Bug 1662087 - Replace explicit error handling involving `mozilla::Result::isErr` with IDB_TRY/IDB_TRY_VAR in ActorsParent.cpp; r=dom-workers-and-storage-reviewers,sg

Differential Revision: https://phabricator.services.mozilla.com/D88864

dom/quota/QuotaCommon.h

@@ -7,6 +7,7 @@
 #ifndef mozilla_dom_quota_quotacommon_h__
 #define mozilla_dom_quota_quotacommon_h__
 
+#include "mozilla/ipc/ProtocolUtils.h"
 #include "nsCOMPtr.h"
 #include "nsDebug.h"
 #include "nsPrintfCString.h"
@@ -729,6 +730,22 @@ auto CollectWhile(const Cond& aCond, const Body& aBody)
   return CollectEach(aCond, [&aBody](bool) { return aBody(); });
 }
 
+template <>
+class MOZ_MUST_USE_TYPE GenericErrorResult<mozilla::ipc::IPCResult> {
+  mozilla::ipc::IPCResult mErrorValue;
+
+  template <typename V, typename E2>
+  friend class Result;
+
+ public:
+  explicit GenericErrorResult(mozilla::ipc::IPCResult aErrorValue)
+      : mErrorValue(aErrorValue) {
+    MOZ_ASSERT(!aErrorValue);
+  }
+
+  operator mozilla::ipc::IPCResult() const { return mErrorValue; }
+};
+
 namespace dom {
 namespace quota {