feat(compiler): add a pseudo $any() function to disable type checking (#20876)

`$any()` can now be used in a binding expression to disable type
checking for the rest of the expression. This similar to `as any` in
TypeScript and allows expression that work at runtime but do not
type-check.

PR Close #20876

packages/compiler/src/compiler_util/expression_converter.ts

@@ -340,6 +340,15 @@ class _AstToIrVisitor implements cdAst.AstVisitor {
   private _getLocal(name: string): o.Expression|null { return this._localResolver.getLocal(name); }
 
   visitMethodCall(ast: cdAst.MethodCall, mode: _Mode): any {
+    if (ast.receiver instanceof cdAst.ImplicitReceiver && ast.name == '$any') {
+      const args = this.visitAll(ast.args, _Mode.Expression) as any[];
+      if (args.length != 1) {
+        throw new Error(
+            `Invalid call to $any, expected 1 argument but received ${args.length || 'none'}`);
+      }
+      return (args[0] as o.Expression).cast(o.DYNAMIC_TYPE);
+    }
+
     const leftMostSafe = this.leftMostSafeNode(ast);
     if (leftMostSafe) {
       return this.convertSafeAccess(ast, leftMostSafe, mode);