Move SessionStorageNamespace entirely into NavigationController and support StoragePartitions.

content/public/browser/content_browser_client.h

Index: content/public/browser/content_browser_client.h
diff --git a/content/public/browser/content_browser_client.h b/content/public/browser/content_browser_client.h
index f5e684979b879e2c627956011e3d03c741494e40..8b9022aff654e7b55b826b24d528fd566e9cd89b 100644
--- a/content/public/browser/content_browser_client.h
+++ b/content/public/browser/content_browser_client.h
@@ -273,6 +273,15 @@ class CONTENT_EXPORT ContentBrowserClient {
   virtual std::string GetStoragePartitionIdForChildProcess(
       content::BrowserContext* browser_context,
       int child_process_id);
+  virtual std::string GetStoragePartitionIdForSiteInstance(
+      content::BrowserContext* browser_context,
+      content::SiteInstance* instance);
+
+  // Allows the embedder to provide a validation check for |partition_id|s.
+  // This domain of valid entries should match the range of outputs for
+  // GetStoragePartitionIdForChildProcess().
+  virtual bool IsValidStoragePartitionId(BrowserContext* browser_context,
+                                         const std::string& partition_id);
 
   // Create and return a new quota permission context.
   virtual QuotaPermissionContext* CreateQuotaPermissionContext();