[llvm] [nfc] Allow forwarding `Error` returns from `Expected` callers (PR #92208)

[Mircea Trofin via llvm-commits]

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@@ -493,11 +493,12 @@ template <class T> class [[nodiscard]] Expected {
 
 public:
   /// Create an Expected<T> error value from the given Error.
-  Expected(Error Err)
+  Expected(Error &&Err)
       : HasError(true)
 #if LLVM_ENABLE_ABI_BREAKING_CHECKS
         // Expected is unchecked upon construction in Debug builds.
-        , Unchecked(true)
+        ,
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mtrofin wrote:

I thought I did - in any case, it may upset the clang-format CI, but I agree formatting should happen in a separate patch.

https://github.com/llvm/llvm-project/pull/92208