Navigation transitions: Place transition page in same process as destination page.

content/public/browser/navigation_controller.h

Index: content/public/browser/navigation_controller.h
diff --git a/content/public/browser/navigation_controller.h b/content/public/browser/navigation_controller.h
index 08ea0b9985df75e9388b91963f6ac7accea1ff82..1b4658cc4f53fef069dabb875b37746a2d617c88 100644
--- a/content/public/browser/navigation_controller.h
+++ b/content/public/browser/navigation_controller.h
@@ -169,6 +169,10 @@ class NavigationController {
     // commits.
     bool should_clear_history_list;
 
+    // Used during a navigation transition. URL to be used when determining
+    // site instance.
+    GURL virtual_url_for_transition;
+
     explicit LoadURLParams(const GURL& url);
     ~LoadURLParams();