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content/browser/browsing_instance.h

Index: content/browser/browsing_instance.h
diff --git a/content/browser/browsing_instance.h b/content/browser/browsing_instance.h
index 0cb80ac80a986940d242d23f538a8460c6bde2dc..1f1199959d857110f466e4802cb601022f97496e 100644
--- a/content/browser/browsing_instance.h
+++ b/content/browser/browsing_instance.h
@@ -73,6 +73,8 @@ class CONTENT_EXPORT BrowsingInstance
   // SiteInstance per site.
   SiteInstance* GetSiteInstanceForURL(const GURL& url);
 
+  SiteInstance* GetSiteInstanceForThirdPartySubframes(const GURL& url);

[Charlie Reis, 2016/03/18 21:15:13]

We might not need this if we don't register subframe sites in the map.

+
   // Adds the given SiteInstance to our map, to ensure that we do not create
   // another SiteInstance for the same site.
   void RegisterSiteInstance(SiteInstance* site_instance);
@@ -120,6 +122,8 @@ class CONTENT_EXPORT BrowsingInstance
   // Number of WebContentses currently using this BrowsingInstance.
   size_t active_contents_count_;
 
+  SiteInstance* site_instance_for_third_party_subframes_ = nullptr;

[Charlie Reis, 2016/03/18 21:15:13]

We probably do want this, as the sole subframe SI (which isn't in the map).

+
   DISALLOW_COPY_AND_ASSIGN(BrowsingInstance);
 };