[Extensions Bindings] Introduce a supportsLazyListeners property

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>
@@ skipping 211 matching lines @@
                                                      context->v8_context()),
       listener_ids,
   };
 
   context->module_system()->CallModuleMethodSafe(
       kEventBindings, "dispatchEvent", arraysize(v8_args), v8_args);
 }
 
 void EventBindings::AttachEventHandler(
     const v8::FunctionCallbackInfo<v8::Value>& args) {
-  CHECK_EQ(1, args.Length());
+  CHECK_EQ(2, args.Length());
   CHECK(args[0]->IsString());
-  AttachEvent(*v8::String::Utf8Value(args[0]));
+  CHECK(args[1]->IsBoolean());
+  AttachEvent(*v8::String::Utf8Value(args[0]), args[1]->BooleanValue());
 }
 
-void EventBindings::AttachEvent(const std::string& event_name) {
+void EventBindings::AttachEvent(const std::string& event_name,
+                                bool supports_lazy_events) {
   if (!context()->HasAccessOrThrowError(event_name))
     return;
 
   // 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.
@@ skipping 11 matching lines @@
                                   : context()->url(),
         event_name, worker_thread_id));
   }
 
   // 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.
   bool is_lazy_context =
       ExtensionFrameHelper::IsContextForEventPage(context()) ||
       context()->context_type() == Feature::SERVICE_WORKER_CONTEXT;
-  if (is_lazy_context) {
+  if (is_lazy_context && supports_lazy_events) {
     if (is_service_worker_context) {
       sender->Send(new ExtensionHostMsg_AddLazyServiceWorkerListener(
           extension_id, event_name, context()->service_worker_scope()));
     } else {
       sender->Send(
           new ExtensionHostMsg_AddLazyListener(extension_id, event_name));
     }
   }
 }
 
 void EventBindings::DetachEventHandler(
     const v8::FunctionCallbackInfo<v8::Value>& args) {
-  CHECK_EQ(2, args.Length());
+  CHECK_EQ(3, args.Length());
   CHECK(args[0]->IsString());
   CHECK(args[1]->IsBoolean());
-  DetachEvent(*v8::String::Utf8Value(args[0]), args[1]->BooleanValue());
+  CHECK(args[2]->IsBoolean());
+  bool was_manual = args[1]->BooleanValue();
+  bool supports_lazy_listeners = args[2]->BooleanValue();
+  DetachEvent(*v8::String::Utf8Value(args[0]),
+              was_manual && supports_lazy_listeners);
 }
 
-void EventBindings::DetachEvent(const std::string& event_name, bool is_manual) {
+void EventBindings::DetachEvent(const std::string& event_name,
+                                bool remove_lazy_listener) {
   // See comment in AttachEvent().
   attached_event_names_.erase(event_name);
 
   int worker_thread_id = content::WorkerThread::GetCurrentId();
   const bool is_service_worker_context = worker_thread_id != kNonWorkerThreadId;
   IPC::Sender* sender = GetIPCSender();
   const std::string& extension_id = context()->GetExtensionID();
 
   if (DecrementEventListenerCount(context(), event_name) == 0) {
     sender->Send(new ExtensionHostMsg_RemoveListener(
         extension_id,
         is_service_worker_context ? context()->service_worker_scope()
                                   : 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 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 (remove_lazy_listener) {
     bool is_lazy_context =
         ExtensionFrameHelper::IsContextForEventPage(context()) ||
         context()->context_type() == Feature::SERVICE_WORKER_CONTEXT;
     if (is_lazy_context) {
       if (is_service_worker_context) {
         sender->Send(new ExtensionHostMsg_RemoveLazyServiceWorkerListener(
             extension_id, event_name, context()->service_worker_scope()));
       } else {
         sender->Send(
             new ExtensionHostMsg_RemoveLazyListener(extension_id, event_name));
       }
     }
   }
 }
 
 // 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 provided to calls to
 // dispatchEvent().
 void EventBindings::AttachFilteredEvent(
     const v8::FunctionCallbackInfo<v8::Value>& args) {
-  CHECK_EQ(2, args.Length());
+  CHECK_EQ(3, args.Length());
   CHECK(args[0]->IsString());
   CHECK(args[1]->IsObject());
+  CHECK(args[2]->IsBoolean());
 
   std::string event_name = *v8::String::Utf8Value(args[0]);
   if (!context()->HasAccessOrThrowError(event_name))
     return;
 
   std::unique_ptr<base::DictionaryValue> filter;
   {
     std::unique_ptr<base::Value> filter_value =
         content::V8ValueConverter::Create()->FromV8Value(
             v8::Local<v8::Object>::Cast(args[1]), context()->v8_context());
     if (!filter_value || !filter_value->IsType(base::Value::Type::DICTIONARY)) {
       args.GetReturnValue().Set(static_cast<int32_t>(-1));
       return;
     }
     filter = base::DictionaryValue::From(std::move(filter_value));
   }
 
+  bool supports_lazy_events = args[2]->BooleanValue();
+
   int id = g_event_filter.Get().AddEventMatcher(
       event_name,
       base::MakeUnique<EventMatcher>(
           std::move(filter), context()->GetRenderFrame()->GetRoutingID()));
   if (id == -1) {
     args.GetReturnValue().Set(static_cast<int32_t>(-1));
     return;
   }
   attached_matcher_ids_.insert(id);
 
   // Only send IPCs the first time a filter gets added.
   const EventMatcher* matcher = g_event_filter.Get().GetEventMatcher(id);
   DCHECK(matcher);
   base::DictionaryValue* filter_weak = matcher->value();
   std::string extension_id = context()->GetExtensionID();
   if (AddFilter(event_name, extension_id, *filter_weak)) {
-    bool lazy = ExtensionFrameHelper::IsContextForEventPage(context());
+    bool lazy = supports_lazy_events &&
+                ExtensionFrameHelper::IsContextForEventPage(context());
     content::RenderThread::Get()->Send(new ExtensionHostMsg_AddFilteredListener(
         extension_id, event_name, *filter_weak, lazy));
   }
 
   args.GetReturnValue().Set(static_cast<int32_t>(id));
 }
 
 void EventBindings::DetachFilteredEventHandler(
     const v8::FunctionCallbackInfo<v8::Value>& args) {
-  CHECK_EQ(2, args.Length());
+  CHECK_EQ(3, args.Length());
   CHECK(args[0]->IsInt32());
   CHECK(args[1]->IsBoolean());
-  DetachFilteredEvent(args[0]->Int32Value(), args[1]->BooleanValue());
+  CHECK(args[2]->IsBoolean());
+  bool was_manual = args[1]->BooleanValue();
+  bool supports_lazy_events = args[2]->BooleanValue();
+  DetachFilteredEvent(args[0]->Int32Value(),
+                      was_manual && supports_lazy_events);
 }
 
-void EventBindings::DetachFilteredEvent(int matcher_id, bool is_manual) {
+void EventBindings::DetachFilteredEvent(int matcher_id,
+                                        bool remove_lazy_event) {
   EventFilter& event_filter = g_event_filter.Get();
   EventMatcher* event_matcher = event_filter.GetEventMatcher(matcher_id);
 
   const std::string& event_name = event_filter.GetEventName(matcher_id);
 
   // Only send IPCs the last time a filter gets removed.
   std::string extension_id = context()->GetExtensionID();
   if (RemoveFilter(event_name, extension_id, event_matcher->value())) {
-    bool remove_lazy =
-        is_manual && ExtensionFrameHelper::IsContextForEventPage(context());
+    bool remove_lazy = remove_lazy_event &&
+                       ExtensionFrameHelper::IsContextForEventPage(context());
     content::RenderThread::Get()->Send(
         new ExtensionHostMsg_RemoveFilteredListener(
             extension_id, event_name, *event_matcher->value(), remove_lazy));
   }
 
   event_filter.RemoveEventMatcher(matcher_id);
   attached_matcher_ids_.erase(matcher_id);
 }
 
 void EventBindings::AttachUnmanagedEvent(
@@ skipping 41 matching lines @@
   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";
 
   g_unmanaged_listeners.Get().erase(context());
 }
 
 }  // namespace extensions