Content API changes to improve DOM stitching in ThreatDetails code.

content/public/browser/render_frame_host.h

Index: content/public/browser/render_frame_host.h
diff --git a/content/public/browser/render_frame_host.h b/content/public/browser/render_frame_host.h
index 72cbc18bbafaea6d07ae5e29f5e9c42fc69c5d0a..53d240d2a8177268f6c75220a9fe018d18e81187 100644
--- a/content/public/browser/render_frame_host.h
+++ b/content/public/browser/render_frame_host.h
@@ -49,6 +49,9 @@ struct FileChooserFileInfo;
 class CONTENT_EXPORT RenderFrameHost : public IPC::Listener,
                                        public IPC::Sender {
  public:
+  // Constant used to denote that a lookup of a FrameTreeNodeId has failed.

[Charlie Reis, 2017/05/05 21:03:08]

nit: FrameTreeNode ID

[lpz, 2017/05/10 14:21:10]

Done.

+  static const int kNoFrameTreeNodeId = -1;
+
   // Returns the RenderFrameHost given its ID and the ID of its render process.
   // Returns nullptr if the IDs do not correspond to a live RenderFrameHost.
   static RenderFrameHost* FromID(int render_process_id, int render_frame_id);
@@ -63,6 +66,11 @@ class CONTENT_EXPORT RenderFrameHost : public IPC::Listener,
   // Returns a RenderFrameHost given its accessibility tree ID.
   static RenderFrameHost* FromAXTreeID(int ax_tree_id);
 
+  // Returns the FrameTreeNodeId of either the RenderFrameHost or the

[Charlie Reis, 2017/05/05 21:03:08]

nit: FrameTreeNode ID

[lpz, 2017/05/10 14:21:09]

Done.

+  // RenderFrameProxyHost related to the specified |process_id| and |routing_id|
+  // pair, depending on whether they identify a local or remote frame.

[Charlie Reis, 2017/05/05 21:03:08]

Let's rephrase, because RenderFrameProxyHost isn't part of the public API and
the term "remote frame" isn't meaningful in the browser process.  Something
like:

Returns the FrameTreeNode ID corresponding to the specified |process_id| and
|routing_id|. This routing ID pair may represent a placeholder for frame that is
currently rendered in a different process than |process_id|.

[lpz, 2017/05/10 14:21:10]

Done, and also changed to return a RenderFrameHost* instead of int as per
dmazonni's suggestion.

+  static int GetFrameTreeNodeIdForRoutingId(int process_id, int routing_id);
+
   ~RenderFrameHost() override {}
 
   // Returns the route id for this frame.