Move MainWorldScriptContext accessor/method from WebFrame to WebLocalFrame.

extensions/renderer/extension_helper.cc

Index: extensions/renderer/extension_helper.cc
diff --git a/extensions/renderer/extension_helper.cc b/extensions/renderer/extension_helper.cc
index d90a34d7066fcc1186acd604aed54accda9a574f..c58c556ebd8eb60b9bc59e54314ceb5cc110afac 100644
--- a/extensions/renderer/extension_helper.cc
+++ b/extensions/renderer/extension_helper.cc
@@ -15,6 +15,7 @@
 #include "extensions/renderer/dispatcher.h"
 #include "third_party/WebKit/public/platform/WebURLRequest.h"
 #include "third_party/WebKit/public/web/WebDocument.h"
+#include "third_party/WebKit/public/web/WebLocalFrame.h"
 #include "third_party/WebKit/public/web/WebView.h"
 
 namespace extensions {
@@ -67,8 +68,15 @@ void ExtensionHelper::OnSetFrameName(const std::string& name) {
 
 void ExtensionHelper::OnAppWindowClosed() {
   v8::HandleScope scope(v8::Isolate::GetCurrent());
-  v8::Local<v8::Context> v8_context =
-      render_view()->GetWebView()->MainFrame()->MainWorldScriptContext();
+  if (!render_view()->GetWebView()->MainFrame()->IsWebLocalFrame()) {

[dcheng, 2017/06/06 19:57:17]

Is this actually something we need to handle? I don't quite understand when this
helper is installed.

[Łukasz Anforowicz, 2017/06/07 20:35:07]

Good point - ExtensionMsg_AppWindowClosed is sent from
AppWindowContentsImpl::NativeWindowClosed and always targets the non-swapped-out
RenderView.  So - I've changed the above into a DCHECK.

+    NOTREACHED();
+    return;
+  }
+  v8::Local<v8::Context> v8_context = render_view()
+                                          ->GetWebView()
+                                          ->MainFrame()
+                                          ->ToWebLocalFrame()
+                                          ->MainWorldScriptContext();
   ScriptContext* script_context =
       dispatcher_->script_context_set().GetByV8Context(v8_context);
   if (!script_context)