Solidify Entry discarding logic (NavigationHandle keeps its ID)

content/browser/frame_host/navigation_handle_impl.h

Index: content/browser/frame_host/navigation_handle_impl.h
diff --git a/content/browser/frame_host/navigation_handle_impl.h b/content/browser/frame_host/navigation_handle_impl.h
index 6248b18accd8b00aeed381575909ca6fac07f16f..6d7e3ecd403445564f5e0007944d84ed32535c17 100644
--- a/content/browser/frame_host/navigation_handle_impl.h
+++ b/content/browser/frame_host/navigation_handle_impl.h
@@ -70,7 +70,8 @@ class CONTENT_EXPORT NavigationHandleImpl : public NavigationHandle {
   static scoped_ptr<NavigationHandleImpl> Create(
       const GURL& url,
       FrameTreeNode* frame_tree_node,
-      const base::TimeTicks& navigation_start);
+      const base::TimeTicks& navigation_start,
+      NavigationEntry* navigation_entry);
   ~NavigationHandleImpl() override;
 
   // NavigationHandle implementation:
@@ -112,6 +113,8 @@ class CONTENT_EXPORT NavigationHandleImpl : public NavigationHandle {
   // in the network stack.
   const net::HttpResponseHeaders* GetResponseHeaders();
 
+  int get_entry_id() { return entry_id_; }

[Charlie Reis, 2016/02/05 19:36:11]

nit: Maybe nav_entry_id(), as in RenderFrameHostImpl?

This would also benefit from a comment about when it's valid, that it's 0 for
invalid, and whether it can change over time.

[Charlie Harrison, 2016/02/05 23:10:23]

I don't *think* it can change over time, so I'll mark it const (and make the
function const too, why not) + added a comment.

+
   void set_net_error_code(net::Error net_error_code) {
     net_error_code_ = net_error_code;
   }
@@ -201,7 +204,8 @@ class CONTENT_EXPORT NavigationHandleImpl : public NavigationHandle {
 
   NavigationHandleImpl(const GURL& url,
                        FrameTreeNode* frame_tree_node,
-                       const base::TimeTicks& navigation_start);
+                       const base::TimeTicks& navigation_start,
+                       NavigationEntry* navigation_entry);
 
   NavigationThrottle::ThrottleCheckResult CheckWillStartRequest();
   NavigationThrottle::ThrottleCheckResult CheckWillRedirectRequest();
@@ -244,6 +248,9 @@ class CONTENT_EXPORT NavigationHandleImpl : public NavigationHandle {
   // The time this navigation started.
   const base::TimeTicks navigation_start_;
 
+  // The unique id of the corresponding NavigationEntry.
+  int entry_id_;
+
   // This callback will be run when all throttle checks have been performed.
   ThrottleChecksFinishedCallback complete_callback_;