Moved NavigationManagerImpl serialization out of CRWSessionController.

ios/web/public/web_state/web_state.h

Index: ios/web/public/web_state/web_state.h
diff --git a/ios/web/public/web_state/web_state.h b/ios/web/public/web_state/web_state.h
index cb31708c492e1c35c175c38871a1731f9e39ba58..87a4c7cbbfaddfa50192c7bd19e940e7940cfe96 100644
--- a/ios/web/public/web_state/web_state.h
+++ b/ios/web/public/web_state/web_state.h
@@ -11,6 +11,7 @@
 #include <vector>
 
 #include "base/callback_forward.h"
+#import "base/mac/scoped_nsobject.h"
 #include "base/memory/weak_ptr.h"
 #include "base/supports_user_data.h"
 #include "ios/web/public/referrer.h"
@@ -24,6 +25,7 @@ class GURL;
 class SkBitmap;
 
 @class CRWJSInjectionReceiver;
+@class CRWNavigationManagerSerialization;
 @protocol CRWScrollableContent;
 @protocol CRWWebViewProxy;
 typedef id<CRWWebViewProxy> CRWWebViewProxyType;
@@ -54,10 +56,15 @@ class WebState : public base::SupportsUserData {
  public:
   // Parameters for the Create() method.
   struct CreateParams {
+    // Constructor used to create new WebStates.
     explicit CreateParams(web::BrowserState* browser_state);
+    // Constructor used to create a WebState with restores session history.
+    explicit CreateParams(web::BrowserState* browser_state,
+                          CRWNavigationManagerSerialization* serialization);

[Eugene But (OOO till 7-30), 2017/01/25 16:03:38]

Content does not have serialized state in CreateParams. Do we have a good reason
to diverge from content? I noticed that they have
WebContents::CreateWithSessionStorage. Do you think CreateWithSessionStorage is
something that we should use on iOS?

Serialization seems like an area where diverging from content is unnecessary.

[kkhorimoto, 2017/01/26 07:19:10]

Done.

     ~CreateParams();
 
     web::BrowserState* browser_state;
+    base::scoped_nsobject<CRWNavigationManagerSerialization> serialization;
   };
 
   // Parameters for the OpenURL() method.
@@ -135,6 +142,11 @@ class WebState : public base::SupportsUserData {
   virtual const NavigationManager* GetNavigationManager() const = 0;
   virtual NavigationManager* GetNavigationManager() = 0;
 
+  // Creates a serialized version of the NavigationManager. The returned value
+  // is autoreleased.
+  virtual CRWNavigationManagerSerialization*
+  BuildSerializedNavigationManager() = 0;
+
   // Gets the CRWJSInjectionReceiver associated with this WebState.
   virtual CRWJSInjectionReceiver* GetJSInjectionReceiver() const = 0;