Fix IsRenderFrameLive and use it in RenderFrameHostManager.

content/browser/frame_host/frame_tree_node.cc

Index: content/browser/frame_host/frame_tree_node.cc
diff --git a/content/browser/frame_host/frame_tree_node.cc b/content/browser/frame_host/frame_tree_node.cc
index ebc542e56e31bb2ac71100892bb80ec38d72d15f..180d8461cb00cc3d930b5a661e097aec6c34612b 100644
--- a/content/browser/frame_host/frame_tree_node.cc
+++ b/content/browser/frame_host/frame_tree_node.cc
@@ -76,6 +76,9 @@ void FrameTreeNode::RemoveChild(FrameTreeNode* child) {
 void FrameTreeNode::ResetForNewProcess() {
   current_url_ = GURL();
 
+  // The RenderFrame no longer exists and will need to be created again.
+  current_frame_host()->set_render_frame_created(false);
+
   // The children may not have been cleared if a cross-process navigation
   // commits before the old process cleans everything up.  Make sure the child
   // nodes get deleted before swapping to a new process.