refactor(types): widen Component type to include consutructor types

returned from `defineComponent`

ref: https://github.com/vuejs/vue-router-next/pull/421
also close #1880

Previous `Component` type is now exported as `ConcreteComponent`.

This introduces a minor breaking change when calling `h(comp, { ... })`
will now fail if `comp` is a of generic `Component` type, since it does
not specify what props it expects.

packages/runtime-core/src/component.ts

@@ -7,14 +7,14 @@ import {
   proxyRefs
 } from '@vue/reactivity'
 import {
-  CreateComponentPublicInstance,
   ComponentPublicInstance,
   PublicInstanceProxyHandlers,
   RuntimeCompiledPublicInstanceProxyHandlers,
   createRenderContext,
   exposePropsOnRenderContext,
-  exposeSetupStateOnRenderContext
-} from './componentProxy'
+  exposeSetupStateOnRenderContext,
+  ComponentPublicInstanceConstructor
+} from './componentPublicInstance'
 import {
   ComponentPropsOptions,
   NormalizedPropsOptions,
@@ -110,21 +110,19 @@ export interface ClassComponent {
   __vccOpts: ComponentOptions
 }
 
-export type Component = ComponentOptions | FunctionalComponent<any, any>
+/**
+ * Concrete component type matches its actual value: it's either an options
+ * object, or a function. Use this where the code expects to work with actual
+ * values, e.g. checking if its a function or not. This is mostly for internal
+ * implementation code.
+ */
+export type ConcreteComponent = ComponentOptions | FunctionalComponent<any, any>
 
-// A type used in public APIs where a component type is expected.
-// The constructor type is an artificial type returned by defineComponent().
-export type PublicAPIComponent =
-  | Component
-  | {
-      new (...args: any[]): CreateComponentPublicInstance<
-        any,
-        any,
-        any,
-        any,
-        any
-      >
-    }
+/**
+ * A type used in public APIs where a component type is expected.
+ * The constructor type is an artificial type returned by defineComponent().
+ */
+export type Component = ConcreteComponent | ComponentPublicInstanceConstructor
 
 export { ComponentOptions }
 
@@ -174,7 +172,7 @@ export type InternalRenderFunction = {
  */
 export interface ComponentInternalInstance {
   uid: number
-  type: Component
+  type: ConcreteComponent
   parent: ComponentInternalInstance | null
   root: ComponentInternalInstance
   appContext: AppContext
@@ -346,7 +344,7 @@ export function createComponentInstance(
   parent: ComponentInternalInstance | null,
   suspense: SuspenseBoundary | null
 ) {
-  const type = vnode.type as Component
+  const type = vnode.type as ConcreteComponent
   // inherit parent app context - or - if root, adopt from root vnode
   const appContext =
     (parent ? parent.appContext : vnode.appContext) || emptyAppContext
@@ -703,7 +701,7 @@ const classify = (str: string): string =>
 /* istanbul ignore next */
 export function formatComponentName(
   instance: ComponentInternalInstance | null,
-  Component: Component,
+  Component: ConcreteComponent,
   isRoot = false
 ): string {
   let name = isFunction(Component)