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

extensions/renderer/event_bindings.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "extensions/renderer/event_bindings.h"
 
 #include <stdint.h>
 
 #include <map>
 #include <memory>
 #include <utility>
 
 #include "base/bind.h"
 #include "base/lazy_instance.h"
 #include "base/memory/ptr_util.h"
 #include "components/crx_file/id_util.h"
 #include "content/public/child/v8_value_converter.h"
 #include "content/public/renderer/render_frame.h"
 #include "content/public/renderer/render_thread.h"
 #include "content/public/renderer/render_view.h"
+#include "extensions/common/constants.h"
 #include "extensions/common/event_filter.h"
 #include "extensions/common/extension.h"
 #include "extensions/common/extension_messages.h"
 #include "extensions/common/value_counter.h"
 #include "extensions/renderer/extension_frame_helper.h"
 #include "extensions/renderer/script_context.h"
+#include "extensions/renderer/service_worker_request_sender.h"
+#include "extensions/renderer/worker_thread_dispatcher.h"
 #include "url/gurl.h"
 
 namespace extensions {
 
 namespace {
 
 // A map of event names to the number of contexts listening to that event.
 // We notify the browser about event listeners when we transition between 0
 // and 1.
 typedef std::map<std::string, int> EventListenerCounts;
@@ skipping 156 matching lines @@
 
   // Record the attachment for this context so that events can be detached when
   // the context is destroyed.
   //
   // Ideally we'd CHECK that it's not already attached, however that's not
   // possible because extensions can create and attach events themselves. Very
   // silly, but that's the way it is. For an example of this, see
   // chrome/test/data/extensions/api_test/events/background.js.
   attached_event_names_.insert(event_name);
 
+  const int worker_thread_id = content::WorkerThread::GetCurrentId();
   const std::string& extension_id = context()->GetExtensionID();
+  const bool is_service_worker_context =
+      context()->context_type() == Feature::SERVICE_WORKER_CONTEXT;
   if (IncrementEventListenerCount(context(), event_name) == 1) {
-    content::RenderThread::Get()->Send(new ExtensionHostMsg_AddListener(
-        extension_id, context()->url(), event_name));
+    if (is_service_worker_context) {

[Devlin, 2017/06/01 04:54:50]

This is a bit painful.  Can we add an IPCSender* and a thread id as members and
use those inline to avoid having two calls in each place?

[lazyboy, 2017/06/01 23:33:29]

I've reworked the code a bit to remove duplicate IPCs. Let me know if that
works.

+      WorkerThreadDispatcher::Get()->GetRequestSender()->SendIPC(
+          new ExtensionHostMsg_AddListener(extension_id, context()->url(),
+                                           event_name, worker_thread_id));
+    } else {
+      content::RenderThread::Get()->Send(new ExtensionHostMsg_AddListener(
+          extension_id, context()->url(), event_name, kNonWorkerThreadId));
+    }
   }
 
   // This is called the first time the page has added a listener. Since
   // the background page is the only lazy page, we know this is the first
   // time this listener has been registered.
   if (ExtensionFrameHelper::IsContextForEventPage(context())) {
-    content::RenderThread::Get()->Send(
-        new ExtensionHostMsg_AddLazyListener(extension_id, event_name));
+    content::RenderThread::Get()->Send(new ExtensionHostMsg_AddLazyListener(
+        extension_id, event_name, worker_thread_id));
+  } else if (is_service_worker_context) {
+    // context()->url() example:
+    // chrome-extension://admhefkdknjikemecnclbacmoefgfbdm/sw.js
+    WorkerThreadDispatcher::Get()->GetRequestSender()->SendIPC(
+        new ExtensionHostMsg_AddLazyListener(extension_id, event_name,
+                                             worker_thread_id));
   }
 }
 
 void EventBindings::DetachEventHandler(
     const v8::FunctionCallbackInfo<v8::Value>& args) {
   CHECK_EQ(2, args.Length());
   CHECK(args[0]->IsString());
   CHECK(args[1]->IsBoolean());
   DetachEvent(*v8::String::Utf8Value(args[0]), args[1]->BooleanValue());
 }
 
 void EventBindings::DetachEvent(const std::string& event_name, bool is_manual) {
   // See comment in AttachEvent().
   attached_event_names_.erase(event_name);
 
+  int worker_thread_id = content::WorkerThread::GetCurrentId();
+  const bool is_service_worker_context =
+      context()->context_type() == Feature::SERVICE_WORKER_CONTEXT;
   const std::string& extension_id = context()->GetExtensionID();
 
   if (DecrementEventListenerCount(context(), event_name) == 0) {
-    content::RenderThread::Get()->Send(new ExtensionHostMsg_RemoveListener(
-        extension_id, context()->url(), event_name));
+    if (is_service_worker_context) {
+      WorkerThreadDispatcher::Get()->GetRequestSender()->SendIPC(
+          new ExtensionHostMsg_RemoveListener(extension_id, context()->url(),
+                                              event_name, worker_thread_id));
+    } else {
+      content::RenderThread::Get()->Send(new ExtensionHostMsg_RemoveListener(
+          extension_id, context()->url(), event_name, worker_thread_id));
+    }
   }
 
   // DetachEvent is called when the last listener for the context is
-  // removed. If the context is the background page, and it removes the
-  // last listener manually, then we assume that it is no longer interested
-  // in being awakened for this event.
-  if (is_manual && ExtensionFrameHelper::IsContextForEventPage(context())) {
-    content::RenderThread::Get()->Send(
-        new ExtensionHostMsg_RemoveLazyListener(extension_id, event_name));
+  // removed. If the context is the background page or service worker, and it
+  // removes the last listener manually, then we assume that it is no longer
+  // interested in being awakened for this event.
+  if (is_manual) {
+    if (is_service_worker_context) {
+      WorkerThreadDispatcher::Get()->GetRequestSender()->SendIPC(
+          new ExtensionHostMsg_RemoveLazyListener(extension_id, event_name,
+                                                  worker_thread_id));
+    } else if (ExtensionFrameHelper::IsContextForEventPage(context())) {
+      content::RenderThread::Get()->Send(
+          new ExtensionHostMsg_RemoveLazyListener(extension_id, event_name,
+                                                  worker_thread_id));
+    }
   }
 }
 
 // MatcherID AttachFilteredEvent(string event_name, object filter)
 // event_name - Name of the event to attach.
 // filter - Which instances of the named event are we interested in.
 // returns the id assigned to the listener, which will be returned from calls
 // to MatchAgainstEventFilter where this listener matches.
 void EventBindings::AttachFilteredEvent(
     const v8::FunctionCallbackInfo<v8::Value>& args) {
@@ skipping 110 matching lines @@
   // Same for filtered events.
   std::set<int> attached_matcher_ids_safe = attached_matcher_ids_;
   for (int matcher_id : attached_matcher_ids_safe) {
     DetachFilteredEvent(matcher_id, false /* is_manual */);
   }
   DCHECK(attached_matcher_ids_.empty())
       << "Filtered events cannot be attached during invalidation";
 }
 
 }  // namespace extensions