Fix RenderFrameCreated and RenderFrameDeleted WebContentsObserver methods

The RenderFrameCreated and RenderFrameDeleted observer methods aren't
matching the lifetime of the renderer-side RenderFrame object. This CL
fixes the methods to be called at the right times to match.

BUG=450799, 425397

Review URL: https://codereview.chromium.org/921443003

Cr-Commit-Position: refs/heads/master@{#317792}
diff --git a/content/public/browser/web_contents.h b/content/public/browser/web_contents.h
index 879e8d8..493abd8 100644
--- a/content/public/browser/web_contents.h
+++ b/content/public/browser/web_contents.h
@@ -122,6 +122,12 @@
     // Used to specify the location context which display the new view should
     // belong. This can be nullptr if not needed.
     gfx::NativeView context;
+
+    // Used to specify that the new WebContents creation is driven by the
+    // renderer process. In this case, the renderer-side objects, such as
+    // RenderFrame, have already been created on the renderer side, and
+    // WebContents construction should take this into account.
+    bool renderer_initiated_creation;
   };
 
   // Creates a new WebContents.