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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..aa4c6e37224f50a355f13ad1da612d033cea9c3c 100644
--- a/content/browser/site_instance_impl.h
+++ b/content/browser/site_instance_impl.h
@@ -44,6 +44,12 @@ class CONTENT_EXPORT SiteInstanceImpl : public SiteInstance,
   size_t GetRelatedActiveContentsCount() override;
   bool RequiresDedicatedProcess() override;
 
+  // Returns the SiteInstance, related to this one, that should be used
+  // for subframes when an oopif is required, but a dedicated process is not.
+  // This SiteInstance will be created if it doesn't already exist. There is
+  // at most one of these per BrowsingInstance.
+  SiteInstance* GetDefaultSubframeSiteInstance();
+
   // 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 +94,10 @@ class CONTENT_EXPORT SiteInstanceImpl : public SiteInstance,
   void AddObserver(Observer* observer);
   void RemoveObserver(Observer* observer);
 
+  bool is_default_subframe_site_instance() {
+    return is_default_subframe_site_instance_;
+  }
+
   // 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 +135,11 @@ class CONTENT_EXPORT SiteInstanceImpl : public SiteInstance,
   // instead.
   explicit SiteInstanceImpl(BrowsingInstance* browsing_instance);
 
+  // Only BrowsingInstance should call this.
+  void set_is_default_subframe_site_instance() {
+    is_default_subframe_site_instance_ = true;
+  }
+
  private:
   // RenderProcessHostObserver implementation.
   void RenderProcessHostDestroyed(RenderProcessHost* host) override;
@@ -146,7 +161,7 @@ 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 +170,18 @@ 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;
+
+  // Whether this SiteInstance is the default subframe SiteInstance for its
+  // BrowsingInstance. Only one SiteInstance per BrowsingInstance can have this
+  // be true.
+  bool is_default_subframe_site_instance_ = false;
 
   base::ObserverList<Observer, true> observers_;