Make printing work better with OOPIF.

content/browser/frame_host/frame_tree.cc

Index: content/browser/frame_host/frame_tree.cc
diff --git a/content/browser/frame_host/frame_tree.cc b/content/browser/frame_host/frame_tree.cc
index 370946e428b8d77be1edc2b815a36d53b1b0ce29..b51cee42ad2b89ec8358903d699dce0f512aa46a 100644
--- a/content/browser/frame_host/frame_tree.cc
+++ b/content/browser/frame_host/frame_tree.cc
@@ -109,7 +109,7 @@ FrameTree::FrameTree(Navigator* navigator,
                               std::string(),
                               std::string(),
                               FrameOwnerProperties())),
-      focused_frame_tree_node_id_(-1),
+      focused_frame_tree_node_id_(FrameTreeNode::kFrameTreeNodeInvalidId),

[nasko, 2016/11/02 04:50:37]

I love that you are fixing code and style along the way, but it will be a
smaller diff to review and keep track of if these were committed separately.

[Lei Zhang, 2016/11/08 11:13:22]

Ack. I'll re-review my own CL and strip off some of the random cleanups in an
upcoming patchset.

       load_progress_(0.0) {}
 
 FrameTree::~FrameTree() {
@@ -381,7 +381,7 @@ void FrameTree::ReleaseRenderViewHostRef(RenderViewHostImpl* render_view_host) {
 
 void FrameTree::FrameRemoved(FrameTreeNode* frame) {
   if (frame->frame_tree_node_id() == focused_frame_tree_node_id_)
-    focused_frame_tree_node_id_ = -1;
+    focused_frame_tree_node_id_ = FrameTreeNode::kFrameTreeNodeInvalidId;
 
   // No notification for the root frame.
   if (!frame->parent()) {