[clang] [clang][Index] Use HeuristicResolver in libIndex (PR #125153)

[Shafik Yaghmour via cfe-commits]

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@@ -25,6 +26,17 @@ static bool isGeneratedDecl(const Decl *D) {
   return false;
 }
 
+IndexingContext::IndexingContext(IndexingOptions IndexOpts,
+                                 IndexDataConsumer &DataConsumer)
+    : IndexOpts(IndexOpts), DataConsumer(DataConsumer) {}
+
+IndexingContext::~IndexingContext() = default;
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shafik wrote:

@HighCommander4 you defaulted the destructor in the source file b/c of the `std::unique_ptr<HeuristicResolver> Resolver` which would require the `HeuristicResolver` to be complete when the destructor is defined, correct? 

This was flagged by static analysis as a rule of three violation but it looks like it makes sense in this case but it should have been explicitly documented with a comment b/c it is not obvious w/o some digging.

https://github.com/llvm/llvm-project/pull/125153