refactor(ivy): clean projection support (#23287)

PR Close #23287

packages/core/src/render3/instructions.ts

@@ -1710,12 +1710,14 @@ export function projection(
   }
 
   if (canInsertNativeNode(currentParent, currentView)) {
+    ngDevMode && assertNodeType(currentParent, LNodeType.Element);
     // process each node in the list of projected nodes:
     let nodeToProject: LNode|null = node.data.head;
     const lastNodeToProject = node.data.tail;
     while (nodeToProject) {
       appendProjectedNode(
-          nodeToProject as LTextNode | LElementNode | LContainerNode, currentParent, currentView);
+          nodeToProject as LTextNode | LElementNode | LContainerNode, currentParent as LElementNode,
+          currentView);
       nodeToProject = nodeToProject === lastNodeToProject ? null : nodeToProject.pNextOrParent;
     }
   }

packages/core/src/render3/node_manipulation.ts

@@ -473,24 +473,24 @@ export function insertChild(node: LNode, currentView: LView): void {
  * @param currentView Current LView
  */
 export function appendProjectedNode(
-    node: LElementNode | LTextNode | LContainerNode, currentParent: LViewNode | LElementNode,
+    node: LElementNode | LTextNode | LContainerNode, currentParent: LElementNode,
     currentView: LView): void {
   if (node.type !== LNodeType.Container) {
     appendChild(currentParent, (node as LElementNode | LTextNode).native, currentView);
-  } else if (canInsertNativeNode(currentParent, currentView)) {
+  } else {
     // The node we are adding is a Container and we are adding it to Element which
     // is not a component (no more re-projection).
     // Alternatively a container is projected at the root of a component's template
     // and can't be re-projected (as not content of any component).
     // Assignee the final projection location in those cases.
     const lContainer = (node as LContainerNode).data;
-    lContainer.renderParent = currentParent as LElementNode;
+    lContainer.renderParent = currentParent;
     const views = lContainer.views;
     for (let i = 0; i < views.length; i++) {
       addRemoveViewFromContainer(node as LContainerNode, views[i], true, null);
     }
   }
   if (node.dynamicLContainerNode) {
-    node.dynamicLContainerNode.data.renderParent = currentParent as LElementNode;
+    node.dynamicLContainerNode.data.renderParent = currentParent;
   }
 }