Moved TabID implementation to SerializableUserData.

ios/chrome/browser/tabs/tab.mm

Index: ios/chrome/browser/tabs/tab.mm
diff --git a/ios/chrome/browser/tabs/tab.mm b/ios/chrome/browser/tabs/tab.mm
index 9c5817c93f2cc87c952e47199a85086a156df635..5ec26ba270e1b77e5e9c14077800a3a04326c7c6 100644
--- a/ios/chrome/browser/tabs/tab.mm
+++ b/ios/chrome/browser/tabs/tab.mm
@@ -133,6 +133,7 @@
 #include "ios/web/public/interstitials/web_interstitial.h"
 #import "ios/web/public/navigation_manager.h"
 #include "ios/web/public/referrer.h"
+#import "ios/web/public/serializable_user_data_manager.h"
 #include "ios/web/public/ssl_status.h"
 #include "ios/web/public/url_scheme_util.h"
 #include "ios/web/public/url_util.h"
@@ -176,6 +177,10 @@
 class FaviconDriverObserverBridge;
 class TabInfoBarObserver;
 
+// The key under which the Tab ID is stored in the WebState's serializable user
+// data.
+NSString* const kTabIDKey = @"TabID";
+
 // Name of histogram for recording the state of the tab when the renderer is
 // terminated.
 const char kRendererTerminationStateHistogram[] =
@@ -789,8 +794,15 @@ - (NSString*)windowName {
 }
 
 - (NSString*)tabId {
-  DCHECK([self navigationManager]);
-  return [[self navigationManager]->GetSessionController() tabId];
+  DCHECK(self.webState);
+  web::SerializableUserDataManager* userDataManager =
+      web::SerializableUserDataManager::FromWebState(self.webState);
+  id<NSCoding> tabId = userDataManager->GetValueForSerializationKey(kTabIDKey);

[Eugene But (OOO till 7-30), 2017/02/13 17:37:57]

s/tabId/tabID

[kkhorimoto, 2017/02/13 23:41:18]

Done.

+  if (!tabId) {
+    tabId = [[NSUUID UUID] UUIDString];
+    userDataManager->AddSerializableData(tabId, kTabIDKey);
+  }
+  return base::mac::ObjCCastStrict<NSString>(tabId);
 }
 
 - (web::WebState*)webState {