fixup! perf(@angular/build): cache transformed configuration in TypeScript compilation

Author: alan-agius4

packages/angular/build/src/tools/angular/compilation/typescript-compilation.ts

@@ -140,19 +140,22 @@ export abstract class TypeScriptCompilation extends AngularCompilation {
         if (this.#extendedConfigCache.has(posixFile)) {
           cacheKey = posixFile;
         } else {
-          // TypeScript lowercases the keys of the extended config cache on case-insensitive operating systems.
+          // Check with lowercased key because TypeScript lowercases the keys
+          // of the extended config cache on case-insensitive operating systems.
           const lowerCasedPosixFile = posixFile.toLowerCase();
           if (this.#extendedConfigCache.has(lowerCasedPosixFile)) {
             cacheKey = lowerCasedPosixFile;
           }
         }
 
-        if (cacheKey) {
-          // If a tsconfig changes, we need to re-read the configuration.
-          this.#cachedConfiguration = undefined;
-          this.#cachedRootFiles = undefined;
-          this.#extendedConfigCache.delete(cacheKey);
+        if (!cacheKey) {
+          continue;
         }
+
+        // If a tsconfig changes, we need to re-read the configuration.
+        this.#cachedConfiguration = undefined;
+        this.#cachedRootFiles = undefined;
+        this.#extendedConfigCache.delete(cacheKey);
       }
     }
   }