Move SessionStorageNamespace entirely into NavigationController and support StoragePartitions.

content/test/test_renderer_host.cc

Index: content/test/test_renderer_host.cc
diff --git a/content/test/test_renderer_host.cc b/content/test/test_renderer_host.cc
index 2e245e6ee298e2272cb9d5613da951d35e6c1a54..81d1d1aa0fcc03bb4ede2838e59eb1b5431acfcf 100644
--- a/content/test/test_renderer_host.cc
+++ b/content/test/test_renderer_host.cc
@@ -118,7 +118,7 @@ WebContents* RenderViewHostTestHarness::CreateTestWebContents() {
   // This will be deleted when the WebContentsImpl goes away.
   SiteInstance* instance = SiteInstance::Create(browser_context_.get());
 
-  return new TestWebContents(browser_context_.get(), instance);
+  return TestWebContents::Create(browser_context_.get(), instance);
 }
 
 void RenderViewHostTestHarness::NavigateAndCommit(const GURL& url) {