PlzNavigate: Initialize the renderer on commit

This CL makes sure that the renderer is initialized before being used to handle
a navigation that has just committed.

BUG=376082

Review URL: https://codereview.chromium.org/536473002

Cr-Commit-Position: refs/heads/master@{#293191}

content/browser/frame_host/render_frame_host_manager.cc

@@ -618,6 +618,20 @@ void RenderFrameHostManager::CommitNavigation(
       render_frame_host_->render_view_host()->AttachToFrameTree();
   }
 
+  // If the renderer that needs to navigate is not live (it was just created or
+  // it crashed), initialize it.
+  if (!render_frame_host_->render_view_host()->IsRenderViewLive()) {
+    // Recreate the opener chain.
+    int opener_route_id = delegate_->CreateOpenerRenderViewsForRenderManager(
+        render_frame_host_->GetSiteInstance());
+    if (!InitRenderView(render_frame_host_->render_view_host(),
+                        opener_route_id,
+                        MSG_ROUTING_NONE,
+                        frame_tree_node_->IsMainFrame())) {
+      return;
+    }
+  }
+
   frame_tree_node_->navigator()->CommitNavigation(
       render_frame_host_.get(), info);
 }

content/browser/frame_host/render_frame_host_manager_unittest.cc

@@ -1758,8 +1758,10 @@ TEST_F(RenderFrameHostManagerTest,
   render_manager->CommitNavigation(commit_info);
   main_request = GetNavigationRequestForRenderFrameManager(render_manager);
 
-  // The main RFH should not have been changed.
+  // The main RFH should not have been changed, and the renderer should have
+  // been initialized.
   EXPECT_EQ(rfh, main_test_rfh());
+  EXPECT_TRUE(main_test_rfh()->render_view_host()->IsRenderViewLive());
 }
 
 // PlzNavigate: Test that a new RenderFrameHost is created when doing a cross
@@ -1791,6 +1793,7 @@ TEST_F(RenderFrameHostManagerTest,
   render_manager->CommitNavigation(commit_info);
   main_request = GetNavigationRequestForRenderFrameManager(render_manager);
   EXPECT_NE(main_test_rfh(), rfh);
+  EXPECT_TRUE(main_test_rfh()->render_view_host()->IsRenderViewLive());
 }
 
 }  // namespace content