Deal with frame removal by content scripts

chrome/renderer/chrome_content_renderer_client.cc

Index: chrome/renderer/chrome_content_renderer_client.cc
diff --git a/chrome/renderer/chrome_content_renderer_client.cc b/chrome/renderer/chrome_content_renderer_client.cc
index d426b37431e0e86f015edc1167f5bb6bef40e2b9..b5254611d80528f0173fcc6b440f9de100806a44 100644
--- a/chrome/renderer/chrome_content_renderer_client.cc
+++ b/chrome/renderer/chrome_content_renderer_client.cc
@@ -1386,6 +1386,22 @@ void ChromeContentRendererClient::AddImageContextMenuProperties(
   }
 }
 
+void ChromeContentRendererClient::AfterDidCreateDocumentElement(
+    content::RenderFrame* render_frame) {
+#if defined(ENABLE_EXTENSIONS)
+  ChromeExtensionsRendererClient::GetInstance()
+      ->AfterDidCreateDocumentElement(render_frame);

[Devlin, 2016/02/12 22:21:56]

hmm... I'd say we should probably mention that |render_frame| can be invalid
after this point (I know it's mentioned elsewhere, but it's good to have it at
the main entry points).

Unfortunately, there's also not really a good way of *checking* if the render
frame is alive at this point - I suppose if we really need to, we could cache
the routing id, and then RenderFrame::FromRoutingID() if we need to (or expose
something from the extensions layer but...yuck).  I suppose I'm fine with
crossing that bridge when we come to it, but it is kind of a shame.

[robwu, 2016/02/12 22:37:13]

Will do.
When it is really needed, we can pass a WeakPtr<RenderFrame> from content/. But
it's not needed at the moment.

[ncarter (slow), 2016/02/16 18:22:32]

If it comes to that, I'd rather we just expose a GetWeakPtr on RenderFrame (as
devlin points out, it's a bit redundant to the routing pair lookup).

For now, documenting up the call stack that "// |frame| may have been deleted."
(as you've done) is probably a best practice.

+#endif
+}
+
+void ChromeContentRendererClient::AfterDidFinishDocumentLoad(
+    content::RenderFrame* render_frame) {
+#if defined(ENABLE_EXTENSIONS)
+  ChromeExtensionsRendererClient::GetInstance()
+      ->AfterDidFinishDocumentLoad(render_frame);
+#endif
+}
+
 void
 ChromeContentRendererClient::DidInitializeServiceWorkerContextOnWorkerThread(
     v8::Local<v8::Context> context,