Extend the ToRenderFrameHost magic to FrameTreeNode* and Shell*

content/browser/web_contents/web_contents_view_aura_browsertest.cc

Index: content/browser/web_contents/web_contents_view_aura_browsertest.cc
diff --git a/content/browser/web_contents/web_contents_view_aura_browsertest.cc b/content/browser/web_contents/web_contents_view_aura_browsertest.cc
index 08b21552c90b57652dc2643a3eac5d16cbb94a30..6d4cb78c5cfe687dd9a3e9cb56252a4826452610 100644
--- a/content/browser/web_contents/web_contents_view_aura_browsertest.cc
+++ b/content/browser/web_contents/web_contents_view_aura_browsertest.cc
@@ -384,9 +384,7 @@ class WebContentsViewAuraTest : public ContentBrowserTest {
   int ExecuteScriptAndExtractInt(const std::string& script) {
     int value = 0;
     EXPECT_TRUE(content::ExecuteScriptAndExtractInt(
-        shell()->web_contents(),
-        "domAutomationController.send(" + script + ")",
-        &value));
+        shell(), "domAutomationController.send(" + script + ")", &value));
     return value;
   }