[llvm] [ctxprof] Use the flattened contextual profile pre-thinlink (PR #134723)

[Snehasish Kumar via llvm-commits]

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@@ -64,7 +64,7 @@ class ProfileSummaryInfo {
   ProfileSummaryInfo(ProfileSummaryInfo &&Arg) = default;
 
   /// If no summary is present, attempt to refresh.
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snehasish wrote:

Update the comment now that we can (optionally) pass a ProfileSummary.

https://github.com/llvm/llvm-project/pull/134723