Use FrameTreeNode ID as frameId in extension APIs

content/browser/frame_host/render_frame_host_impl.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/frame_host/render_frame_host_impl.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/containers/hash_tables.h"
 #include "base/lazy_instance.h"
@@ skipping 116 matching lines @@
   return rfh_state == STATE_DEFAULT;
 }
 
 // static
 RenderFrameHost* RenderFrameHost::FromID(int render_process_id,
                                          int render_frame_id) {
   return RenderFrameHostImpl::FromID(render_process_id, render_frame_id);
 }
 
 // static
+RenderFrameHost* RenderFrameHost::FromFrameTreeNodeID(int frame_tree_node_id) {
+  return RenderFrameHostImpl::FromFrameTreeNodeID(frame_tree_node_id);
+}
+
+// static
 void RenderFrameHost::AllowInjectingJavaScriptForAndroidWebView() {
   g_allow_injecting_javascript = true;
 }
 
 // static
 RenderFrameHostImpl* RenderFrameHostImpl::FromID(int process_id,
                                                  int routing_id) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
   RoutingIDFrameMap* frames = g_routing_id_frame_map.Pointer();
   RoutingIDFrameMap::iterator it = frames->find(
       RenderFrameHostID(process_id, routing_id));
   return it == frames->end() ? NULL : it->second;
 }
 
 // static
+RenderFrameHostImpl* RenderFrameHostImpl::FromFrameTreeNodeID(
+    int frame_tree_node_id) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  FrameTreeNode* frame_tree_node =
+      FrameTreeNode::GloballyFindByID(frame_tree_node_id);
+  return frame_tree_node ? frame_tree_node->current_frame_host() : nullptr;
+}
+
+// static
 RenderFrameHost* RenderFrameHost::FromAXTreeID(
     int ax_tree_id) {
   return RenderFrameHostImpl::FromAXTreeID(ax_tree_id);
 }
 
 // static
 RenderFrameHostImpl* RenderFrameHostImpl::FromAXTreeID(
     AXTreeIDRegistry::AXTreeID ax_tree_id) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
   AXTreeIDRegistry::FrameID frame_id =
@@ skipping 104 matching lines @@
   return process_;
 }
 
 RenderFrameHost* RenderFrameHostImpl::GetParent() {
   FrameTreeNode* parent_node = frame_tree_node_->parent();
   if (!parent_node)
     return NULL;
   return parent_node->current_frame_host();
 }
 
+RenderFrameHost* RenderFrameHostImpl::FindByFrameTreeNodeID(
+    int frame_tree_node_id) {
+  FrameTreeNode* child =
+      frame_tree_node_->frame_tree()->FindByID(frame_tree_node_id);

[Charlie Reis, 2015/10/30 23:25:09]

This doesn't quite match the documentation, which says that it only returns this
node or one of its children.  This code could return a parent if called on a
subframe.

If you're just looking to return a frame from the current frame tree, I might
suggest putting the method on WebContents instead?

[robwu, 2015/10/31 00:10:45]

I was reading frame_tree() as the frame tree rooted at the given node. If that's
incorrect, what do you suggest if I really want to look at the node and its
descendants only?

[robwu, 2015/11/02 19:08:34]

Done.

[Charlie Reis, 2015/11/03 00:23:49]

No, a FrameTree represents the whole tree, starting from the root (main frame).
Hopefully this isn't needed anymore, but you could recursively traverse the
children of the FrameTreeNode if you needed it.

+  return child ? child->current_frame_host() : nullptr;
+}
+
+int RenderFrameHostImpl::GetFrameTreeNodeID() {
+  return frame_tree_node_->frame_tree_node_id();
+}
+
 const std::string& RenderFrameHostImpl::GetFrameName() {
   return frame_tree_node_->frame_name();
 }
 
 bool RenderFrameHostImpl::IsCrossProcessSubframe() {
   FrameTreeNode* parent_node = frame_tree_node_->parent();
   if (!parent_node)
     return false;
   return GetSiteInstance() !=
       parent_node->current_frame_host()->GetSiteInstance();
@@ skipping 1981 matching lines @@
             BrowserPluginInstanceIDToAXTreeID(value)));
         break;
       case AX_CONTENT_INT_ATTRIBUTE_LAST:
         NOTREACHED();
         break;
     }
   }
 }
 
 }  // namespace content