[extension SW]: Support event listener registration and event dispatching.

extensions/renderer/extension_frame_helper.cc

Index: extensions/renderer/extension_frame_helper.cc
diff --git a/extensions/renderer/extension_frame_helper.cc b/extensions/renderer/extension_frame_helper.cc
index da47e687f5662c0d8eefb6830a860edf971c2689..524c960acce6023ae532e8fc8af14074d6b271fa 100644
--- a/extensions/renderer/extension_frame_helper.cc
+++ b/extensions/renderer/extension_frame_helper.cc
@@ -7,6 +7,7 @@
 #include "base/metrics/histogram_macros.h"
 #include "base/strings/string_util.h"
 #include "base/timer/elapsed_timer.h"
+#include "content/public/child/worker_thread.h"
 #include "content/public/renderer/render_frame.h"
 #include "extensions/common/api/messaging/message.h"
 #include "extensions/common/api/messaging/port_id.h"
@@ -148,6 +149,14 @@ bool ExtensionFrameHelper::IsContextForEventPage(const ScriptContext* context) {
               VIEW_TYPE_EXTENSION_BACKGROUND_PAGE;
 }
 
+bool ExtensionFrameHelper::IsContextForSW(const ScriptContext& context) {

[Devlin, 2017/05/24 17:58:25]

We already have context_type() on ScriptContext; do we need this?  If so, we
should move it to ScriptContext, since it's very weird to query the frame
helper, when, by definition, service workers don't run in a frame.

[lazyboy, 2017/05/25 01:33:43]

context_type() should be fine, thanks.
Done.

+  if (content::WorkerThread::GetCurrentId() != 0) {
+    DCHECK(context.GetRenderFrame() == nullptr);
+    return true;
+  }
+  return false;
+}
+
 void ExtensionFrameHelper::DidCreateDocumentElement() {
   did_create_current_document_element_ = true;
   extension_dispatcher_->DidCreateDocumentElement(