Enable swapping a frame back in to its parent process

content/browser/site_per_process_browsertest.cc

Index: content/browser/site_per_process_browsertest.cc
diff --git a/content/browser/site_per_process_browsertest.cc b/content/browser/site_per_process_browsertest.cc
index 465fed363fb06e5615697ef151b5a65ac3b7eba4..a49b7d1e2cd41058bbb6223ae5728cba66490a0a 100644
--- a/content/browser/site_per_process_browsertest.cc
+++ b/content/browser/site_per_process_browsertest.cc
@@ -362,13 +362,12 @@ IN_PROC_BROWSER_TEST_F(SitePerProcessBrowserTest, MAYBE_NavigateRemoteFrame) {
   EXPECT_NE(site_instance,
             child->current_frame_host()->GetSiteInstance());
 
-  // TODO(japhet): This currently causes an assertion in the renderer process.
-  // Enable when the assertion is fixed.
-  //NavigateFrameToURL(child, http_url);
-  //EXPECT_EQ(http_url, observer.navigation_url());
-  //EXPECT_TRUE(observer.navigation_succeeded());
-  //EXPECT_EQ(shell()->web_contents()->GetSiteInstance(),
-  //          child->current_frame_host()->GetSiteInstance());
+  // Navigate back into the original process
+  NavigateFrameToURL(child, http_url);
+  EXPECT_EQ(http_url, observer.navigation_url());
+  EXPECT_TRUE(observer.navigation_succeeded());
+  EXPECT_EQ(shell()->web_contents()->GetSiteInstance(),
+            child->current_frame_host()->GetSiteInstance());
 }
 
 // Crash a subframe and ensures its children are cleared from the FrameTree.