PlzNavigate: ensure we don't create extra-processes for ServiceWorkers

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 34c1f073bbd852c260aecf8eade45656d6d10005..d6c72271d7b13e89eeeffeabc7bfae01c142f42d 100644
--- a/content/browser/browsing_instance.h
+++ b/content/browser/browsing_instance.h
@@ -6,6 +6,7 @@
 #define CONTENT_BROWSER_BROWSING_INSTANCE_H_
 
 #include <stddef.h>
+#include <set>
 
 #include "base/containers/hash_tables.h"
 #include "base/gtest_prod_util.h"
@@ -64,6 +65,12 @@ class CONTENT_EXPORT BrowsingInstance final
   FRIEND_TEST_ALL_PREFIXES(SiteInstanceTest,
                            OneSiteInstancePerSiteInBrowserContext);
 
+  // Lookup for a SiteInstance associated to |url| among all the
+  // BrowsingInstances that belongs to |browser_context|.
+  static scoped_refptr<SiteInstanceImpl> FindSiteInstance(
+      BrowserContext* browser_context,
+      const GURL& url);
+
   // Create a new BrowsingInstance.
   explicit BrowsingInstance(BrowserContext* context);
 
@@ -97,6 +104,10 @@ class CONTENT_EXPORT BrowsingInstance final
   // BrowsingInstance.
   void UnregisterSiteInstance(SiteInstanceImpl* site_instance);
 
+  void RegisterUsedFor(SiteInstanceImpl* site_instance, std::string site);
+  void UnregisterUsedFor(SiteInstanceImpl* site_instance,
+                         const std::set<std::string>& sites);
+
   // Tracks the number of WebContents currently in this BrowsingInstance.
   size_t active_contents_count() const { return active_contents_count_; }
   void increment_active_contents_count() { active_contents_count_++; }
@@ -122,6 +133,11 @@ class CONTENT_EXPORT BrowsingInstance final
   // site, such as about:blank.  See NavigatorImpl::ShouldAssignSiteForURL.
   SiteInstanceMap site_instance_map_;
 
+  // Keeps track of all the SiteInstances that displayed which sites.
+  using SiteToSiteInstanceMap =
+      std::map<std::string, std::set<SiteInstanceImpl*>>;
+  SiteToSiteInstanceMap site_to_site_instance_map_;
+
   // Number of WebContentses currently using this BrowsingInstance.
   size_t active_contents_count_;