Switch to sparse array for deferred nodes.

Author: DanielRosenwasser

src/compiler/checker.ts

@@ -40317,8 +40317,8 @@ namespace ts {
             const enclosingFile = getSourceFileOfNode(node);
             const links = getNodeLinks(enclosingFile);
             if (!(links.flags & NodeCheckFlags.TypeChecked)) {
-                links.deferredNodes ||= new Set();
-                links.deferredNodes.add(node);
+                links.deferredNodes ||= [];
+                links.deferredNodes[getNodeId(node)] = node;
             }
         }
 

src/compiler/types.ts

@@ -5106,7 +5106,7 @@ namespace ts {
         jsxNamespace?: Symbol | false;      // Resolved jsx namespace symbol for this node
         jsxImplicitImportContainer?: Symbol | false; // Resolved module symbol the implicit jsx import of this file should refer to
         contextFreeType?: Type;             // Cached context-free type used by the first pass of inference; used when a function's return is partially contextually sensitive
-        deferredNodes?: Set<Node>; // Set of nodes whose checking has been deferred
+        deferredNodes?: Node[];             // Sparse array of nodes whose checking has been deferred
         capturedBlockScopeBindings?: Symbol[]; // Block-scoped bindings captured beneath this part of an IterationStatement
         outerTypeParameters?: TypeParameter[]; // Outer type parameters of anonymous object type
         isExhaustive?: boolean;             // Is node an exhaustive switch statement