Revert of Move the event attach/detach logic on unload from event.js to

extensions/renderer/event_bindings.cc

Index: extensions/renderer/event_bindings.cc
diff --git a/extensions/renderer/event_bindings.cc b/extensions/renderer/event_bindings.cc
index 472f369063efe82a074811b1ac52f0881f440c80..8a005aaec229225b10432440a1a09772ee8af28b 100644
--- a/extensions/renderer/event_bindings.cc
+++ b/extensions/renderer/event_bindings.cc
@@ -5,6 +5,9 @@
 #include "extensions/renderer/event_bindings.h"
 
 #include <map>
+#include <set>
+#include <string>
+#include <vector>
 
 #include "base/basictypes.h"
 #include "base/bind.h"
@@ -21,7 +24,9 @@
 #include "extensions/common/value_counter.h"
 #include "extensions/renderer/dispatcher.h"
 #include "extensions/renderer/extension_helper.h"
+#include "extensions/renderer/object_backed_native_handler.h"
 #include "url/gurl.h"
+#include "v8/include/v8.h"
 
 namespace extensions {
 
@@ -138,10 +143,12 @@
 
 EventBindings::EventBindings(Dispatcher* dispatcher, ScriptContext* context)
     : ObjectBackedNativeHandler(context), dispatcher_(dispatcher) {
-  RouteFunction("AttachEvent", base::Bind(&EventBindings::AttachEventHandler,
-                                          base::Unretained(this)));
-  RouteFunction("DetachEvent", base::Bind(&EventBindings::DetachEventHandler,
-                                          base::Unretained(this)));
+  RouteFunction(
+      "AttachEvent",
+      base::Bind(&EventBindings::AttachEvent, base::Unretained(this)));
+  RouteFunction(
+      "DetachEvent",
+      base::Bind(&EventBindings::DetachEvent, base::Unretained(this)));
   RouteFunction(
       "AttachFilteredEvent",
       base::Bind(&EventBindings::AttachFilteredEvent, base::Unretained(this)));
@@ -151,35 +158,20 @@
   RouteFunction("MatchAgainstEventFilter",
                 base::Bind(&EventBindings::MatchAgainstEventFilter,
                            base::Unretained(this)));
-
-  // It's safe to use base::Unretained here because |context| will always
-  // outlive us.
-  context->AddInvalidationObserver(
-      base::Bind(&EventBindings::OnInvalidated, base::Unretained(this)));
 }
 
 EventBindings::~EventBindings() {}
 
-void EventBindings::AttachEventHandler(
+// Attach an event name to an object.
+void EventBindings::AttachEvent(
     const v8::FunctionCallbackInfo<v8::Value>& args) {
   CHECK_EQ(1, args.Length());
   CHECK(args[0]->IsString());
-  AttachEvent(*v8::String::Utf8Value(args[0]));
-}
-
-void EventBindings::AttachEvent(const std::string& event_name) {
-  // This method throws an exception if it returns false.
+
+  std::string event_name = *v8::String::Utf8Value(args[0]);
+
   if (!dispatcher_->CheckContextAccessToExtensionAPI(event_name, context()))
     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.
-  attached_event_names_.insert(event_name);
 
   const std::string& extension_id = context()->GetExtensionID();
   if (IncrementEventListenerCount(context(), event_name) == 1) {
@@ -197,20 +189,16 @@
   }
 }
 
-void EventBindings::DetachEventHandler(
+void EventBindings::DetachEvent(
     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);
+
+  std::string event_name = *v8::String::Utf8Value(args[0]);
+  bool is_manual = args[1]->BooleanValue();
 
   const std::string& extension_id = context()->GetExtensionID();
-
   if (DecrementEventListenerCount(context(), event_name) == 0) {
     content::RenderThread::Get()->Send(new ExtensionHostMsg_RemoveListener(
         extension_id, context()->GetURL(), event_name));
@@ -336,15 +324,4 @@
       context()->GetRenderView()->GetRoutingID()));
 }
 
-void EventBindings::OnInvalidated() {
-  // Detach all attached events that weren't attached. Iterate over a copy
-  // because it will be mutated.
-  std::set<std::string> attached_event_names_safe = attached_event_names_;
-  for (const std::string& event_name : attached_event_names_safe) {
-    DetachEvent(event_name, false /* is_manual */);
-  }
-  DCHECK(attached_event_names_.empty())
-      << "Events cannot be attached during invalidation";
-}
-
 }  // namespace extensions