<pre><pre>mountComponent</pre></pre>
callHook(vm, 'beforeMounted')
<pre><pre><span>updateComponent </span><span>= </span><span>() </span><span>=> </span><span>{<br></span><span> </span><span>vm</span><span>.</span>_update<span>(</span>vnode, hydrating)</pre><pre><span>}</span></pre></pre>
入参
_render
<pre>vnode = render.call(vm._renderProxy, vm.$createElement)</pre>
__patch__
<pre><span>vm</span><span>.</span>_watcher <span>= </span><span>new </span><span>Watcher</span><span>(</span><span>vm</span><span>, </span><span>updateComponent</span><span>, </span>noop<span>)</span></pre>
