Add the navigation redirect-chain to Sync sessions proto for offline analysis.

content/browser/frame_host/navigation_entry_impl.h

Index: content/browser/frame_host/navigation_entry_impl.h
diff --git a/content/browser/frame_host/navigation_entry_impl.h b/content/browser/frame_host/navigation_entry_impl.h
index 8a518888ce557ed2d7c47aae34b6e37a1e15843b..3eca1280150c4fc3fb3cde24ef2a812f19cbdb58 100644
--- a/content/browser/frame_host/navigation_entry_impl.h
+++ b/content/browser/frame_host/navigation_entry_impl.h
@@ -86,6 +86,8 @@ class CONTENT_EXPORT NavigationEntryImpl
   virtual void ClearExtraData(const std::string& key) OVERRIDE;
   virtual void SetHttpStatusCode(int http_status_code) OVERRIDE;
   virtual int GetHttpStatusCode() const OVERRIDE;
+  virtual void SetRedirectChain(const std::vector<GURL>& redirects) OVERRIDE;
+  virtual const std::vector<GURL>& GetRedirectChain() const OVERRIDE;
 
   // Once a navigation entry is committed, we should no longer track several
   // pieces of non-persisted state, as documented on the members below.
@@ -192,16 +194,6 @@ class CONTENT_EXPORT NavigationEntryImpl
     should_replace_entry_ = should_replace_entry;
   }
 
-  // Any redirects present in a pending entry when it is transferred from one
-  // process to another.  Not valid after commit.
-  const std::vector<GURL>& redirect_chain() const {
-    return redirect_chain_;
-  }
-
-  void set_redirect_chain(const std::vector<GURL>& redirect_chain) {
-    redirect_chain_ = redirect_chain;
-  }
-
   void SetScreenshotPNGData(scoped_refptr<base::RefCountedBytes> png_data);
   const scoped_refptr<base::RefCountedBytes> screenshot() const {
     return screenshot_;
@@ -257,6 +249,7 @@ class CONTENT_EXPORT NavigationEntryImpl
   bool is_overriding_user_agent_;
   base::Time timestamp_;
   int http_status_code_;
+  std::vector<GURL> redirect_chain_;
 
   // This member is not persisted with session restore because it is transient.
   // If the post request succeeds, this field is cleared since the same
@@ -313,10 +306,6 @@ class CONTENT_EXPORT NavigationEntryImpl
   // doing the redirect).
   bool should_replace_entry_;
 
-  // This is used when transferring a pending entry from one process to another.
-  // It is cleared in |ResetForCommit| and should not be persisted.
-  std::vector<GURL> redirect_chain_;
-
   // This is set to true when this entry's navigation should clear the session
   // history both on the renderer and browser side. The browser side history
   // won't be cleared until the renderer has committed this navigation. This