Clean up lexical classifier (#20123)

Author: Andy

src/compiler/core.ts

@@ -1260,10 +1260,12 @@ namespace ts {
         return result;
     }
 
-    export function arrayToNumericMap<T>(array: ReadonlyArray<T>, makeKey: (value: T) => number): T[] {
-        const result: T[] = [];
+    export function arrayToNumericMap<T>(array: ReadonlyArray<T>, makeKey: (value: T) => number): T[];
+    export function arrayToNumericMap<T, V>(array: ReadonlyArray<T>, makeKey: (value: T) => number, makeValue: (value: T) => V): V[];
+    export function arrayToNumericMap<T, V>(array: ReadonlyArray<T>, makeKey: (value: T) => number, makeValue?: (value: T) => V): V[] {
+        const result: V[] = [];
         for (const value of array) {
-            result[makeKey(value)] = value;
+            result[makeKey(value)] = makeValue ? makeValue(value) : value as any as V;
         }
         return result;
     }

src/compiler/utilities.ts

@@ -5078,16 +5078,7 @@ namespace ts {
     }
 
     export function isStringTextContainingNode(node: Node) {
-        switch (node.kind) {
-            case SyntaxKind.StringLiteral:
-            case SyntaxKind.TemplateHead:
-            case SyntaxKind.TemplateMiddle:
-            case SyntaxKind.TemplateTail:
-            case SyntaxKind.NoSubstitutionTemplateLiteral:
-                return true;
-            default:
-                return false;
-        }
+        return node.kind === SyntaxKind.StringLiteral || isTemplateLiteralKind(node.kind);
     }
 
     // Identifiers