chore: fix build (#2856)

Can't declare 'protected ref' on one class and then 'public ref' on a
subclass.

Remove the shared base base class 'ref' because it's not very useful
anyway and only used in one place.

Conditions shouldn't be `CfnRefElements`, because they can't be
`{ Ref }`ed.

packages/@aws-cdk/cdk/lib/cfn-condition.ts

@@ -1,4 +1,4 @@
-import { CfnRefElement } from './cfn-element';
+import { CfnElement } from './cfn-element';
 import { Construct } from './construct';
 import { IResolvable, IResolveContext } from './resolvable';
 
@@ -15,7 +15,7 @@ export interface CfnConditionProps {
  * Represents a CloudFormation condition, for resources which must be conditionally created and
  * the determination must be made at deploy time.
  */
-export class CfnCondition extends CfnRefElement implements ICfnConditionExpression, IResolvable {
+export class CfnCondition extends CfnElement implements ICfnConditionExpression, IResolvable {
   public readonly displayHint: string | undefined;
 
   /**

packages/@aws-cdk/cdk/lib/cfn-element.ts

@@ -138,13 +138,6 @@ export abstract class CfnElement extends Construct {
     }
   }
 
-  /**
-   * Return a token that will CloudFormation { Ref } this stack element
-   */
-  protected get ref(): IResolvable {
-    return CfnReference.for(this, 'Ref');
-  }
-
   /**
    * Called during synthesize to render the logical ID of this element. If
    * `overrideLogicalId` was it will be used, otherwise, we will allocate the
@@ -174,7 +167,7 @@ export abstract class CfnRefElement extends CfnElement {
    * Return a token that will CloudFormation { Ref } this stack element
    */
   public get ref(): IResolvable {
-    return super.ref;
+    return CfnReference.for(this, 'Ref');
   }
 
   /**

packages/@aws-cdk/cdk/lib/cfn-parameter.ts

@@ -1,5 +1,6 @@
 import { CfnElement } from './cfn-element';
 import { Construct } from './construct';
+import { CfnReference } from './private/cfn-reference';
 import { IResolvable, IResolveContext } from './resolvable';
 import { Token } from './token';
 
@@ -125,7 +126,7 @@ export class CfnParameter extends CfnElement implements IResolvable {
    * The parameter value as a Token
    */
   public get value(): IResolvable {
-    return super.ref;
+    return CfnReference.for(this, 'Ref');
   }
 
   /**
@@ -135,7 +136,7 @@ export class CfnParameter extends CfnElement implements IResolvable {
     if (!isStringType(this.type)) {
       throw new Error(`Parameter type (${this.type}) is not a string type`);
     }
-    return Token.asString(this.ref);
+    return Token.asString(this.value);
   }
 
   /**
@@ -145,7 +146,7 @@ export class CfnParameter extends CfnElement implements IResolvable {
     if (!isListType(this.type)) {
       throw new Error(`Parameter type (${this.type}) is not a string list type`);
     }
-    return Token.asList(this.ref);
+    return Token.asList(this.value);
   }
 
   /**
@@ -155,7 +156,7 @@ export class CfnParameter extends CfnElement implements IResolvable {
     if (!isNumberType(this.type)) {
       throw new Error(`Parameter type (${this.type}) is not a number type`);
     }
-    return Token.asNumber(this.ref);
+    return Token.asNumber(this.value);
   }
 
   /**
@@ -182,7 +183,7 @@ export class CfnParameter extends CfnElement implements IResolvable {
   }
 
   public resolve(_context: IResolveContext): any {
-    return this.ref;
+    return this.value;
   }
 }