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content/browser/site_instance_impl.h

Index: content/browser/site_instance_impl.h
diff --git a/content/browser/site_instance_impl.h b/content/browser/site_instance_impl.h
index 81967cfffa12d827d3e8c35687ee63d9c6ac4fed..7b7944457b890ad93dce457d3736c5d6d23c490e 100644
--- a/content/browser/site_instance_impl.h
+++ b/content/browser/site_instance_impl.h
@@ -44,6 +44,8 @@ class CONTENT_EXPORT SiteInstanceImpl : public SiteInstance,
   size_t GetRelatedActiveContentsCount() override;
   bool RequiresDedicatedProcess() override;
 
+  SiteInstance* GetRelatedSiteInstanceForThirdPartySubframes(const GURL& url);

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

Maybe drop "Related" and |url|?

+
   // Set the web site that this SiteInstance is rendering pages for.
   // This includes the scheme and registered domain, but not the port.  If the
   // URL does not have a valid registered domain, then the full hostname is
@@ -88,6 +90,8 @@ class CONTENT_EXPORT SiteInstanceImpl : public SiteInstance,
   void AddObserver(Observer* observer);
   void RemoveObserver(Observer* observer);
 
+  bool is_for_third_party_subframes() { return is_for_third_party_subframes_; }
+
   // Sets the global factory used to create new RenderProcessHosts.  It may be
   // NULL, in which case the default RenderProcessHost will be created (this is
   // the behavior if you don't call this function).  The factory must be set
@@ -125,6 +129,12 @@ class CONTENT_EXPORT SiteInstanceImpl : public SiteInstance,
   // instead.
   explicit SiteInstanceImpl(BrowsingInstance* browsing_instance);
 
+  // Only BrowsingInstance should call this.
+  void set_is_for_third_party_subframes() {
+    CHECK(!HasSite());
+    is_for_third_party_subframes_ = true;
+  }
+
  private:
   // RenderProcessHostObserver implementation.
   void RenderProcessHostDestroyed(RenderProcessHost* host) override;
@@ -146,7 +156,7 @@ class CONTENT_EXPORT SiteInstanceImpl : public SiteInstance,
   int32_t id_;
 
   // The number of active frames in this SiteInstance.
-  size_t active_frame_count_;
+  size_t active_frame_count_ = 0;
 
   // BrowsingInstance to which this SiteInstance belongs.
   scoped_refptr<BrowsingInstance> browsing_instance_;
@@ -155,13 +165,14 @@ class CONTENT_EXPORT SiteInstanceImpl : public SiteInstance,
   // This pointer will only change once the RenderProcessHost is destructed.  It
   // will still remain the same even if the process crashes, since in that
   // scenario the RenderProcessHost remains the same.
-  RenderProcessHost* process_;
+  RenderProcessHost* process_ = nullptr;
 
   // The web site that this SiteInstance is rendering pages for.
   GURL site_;
 
   // Whether SetSite has been called.
-  bool has_site_;
+  bool has_site_ = false;
+  bool is_for_third_party_subframes_ = false;
 
   base::ObserverList<Observer, true> observers_;