Unbreak tabs.onRemove extension API in face of fast tab closure

chrome/browser/extensions/browser_event_router.cc

Index: chrome/browser/extensions/browser_event_router.cc
diff --git a/chrome/browser/extensions/browser_event_router.cc b/chrome/browser/extensions/browser_event_router.cc
index d2c8b5de13864b2abdf83a05844bff928db3f5b0..2caecc41af66170f6971bfdbde48216cb9a33ab3 100644
--- a/chrome/browser/extensions/browser_event_router.cc
+++ b/chrome/browser/extensions/browser_event_router.cc
@@ -20,6 +20,7 @@
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_iterator.h"
 #include "chrome/browser/ui/browser_list.h"
+#include "chrome/browser/ui/tab_contents/core_tab_helper.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/common/chrome_notification_types.h"
 #include "chrome/common/extensions/api/extension_action/action_info.h"
@@ -215,50 +216,31 @@ void BrowserEventRouter::TabInsertedAt(WebContents* contents,
                 EventRouter::USER_GESTURE_UNKNOWN);
 }
 
-void BrowserEventRouter::TabDetachedAt(WebContents* contents, int index) {
+void BrowserEventRouter::TabDetachedAt(WebContents* contents,
+                                       int index,
+                                       bool closing_all) {
   if (!GetTabEntry(contents)) {
-    // The tab was removed. Don't send detach event.
+    // The tab was removed. Don't send detach/remove event.
     return;
   }
 
-  scoped_ptr<ListValue> args(new ListValue());
-  args->Append(Value::CreateIntegerValue(ExtensionTabUtil::GetTabId(contents)));
-
-  DictionaryValue* object_args = new DictionaryValue();
-  object_args->Set(tab_keys::kOldWindowIdKey, Value::CreateIntegerValue(
-      ExtensionTabUtil::GetWindowIdOfTab(contents)));
-  object_args->Set(tab_keys::kOldPositionKey, Value::CreateIntegerValue(
-      index));
-  args->Append(object_args);
-
-  Profile* profile = Profile::FromBrowserContext(contents->GetBrowserContext());
-  DispatchEvent(profile, events::kOnTabDetached, args.Pass(),
-                EventRouter::USER_GESTURE_UNKNOWN);
+  // If this detach is occuring as part of the process of closing |contents|
+  // then dispatch a remove event rather than a detach event.
+  CoreTabHelper* core_tab_helper = CoreTabHelper::FromWebContents(contents);
+  if (core_tab_helper->GetWebContentsDetachedToClose()) {
+    int tab_id = ExtensionTabUtil::GetTabId(contents);
+    DispatchTabRemovedAndUnregisterNotifications(contents, tab_id, closing_all);
+  } else {
+    DispatchTabDetached(contents, index);
+  }
 }
 
 void BrowserEventRouter::TabClosingAt(TabStripModel* tab_strip_model,
                                       WebContents* contents,
                                       int index) {
   int tab_id = ExtensionTabUtil::GetTabId(contents);
-
-  scoped_ptr<ListValue> args(new ListValue());
-  args->Append(Value::CreateIntegerValue(tab_id));
-
-  DictionaryValue* object_args = new DictionaryValue();
-  object_args->SetInteger(tab_keys::kWindowIdKey,
-                          ExtensionTabUtil::GetWindowIdOfTab(contents));
-  object_args->SetBoolean(tab_keys::kWindowClosing,
-                          tab_strip_model->closing_all());
-  args->Append(object_args);
-
-  Profile* profile = Profile::FromBrowserContext(contents->GetBrowserContext());
-  DispatchEvent(profile, events::kOnTabRemoved, args.Pass(),
-                EventRouter::USER_GESTURE_UNKNOWN);
-
-  int removed_count = tab_entries_.erase(tab_id);
-  DCHECK_GT(removed_count, 0);
-
-  UnregisterForTabNotifications(contents);
+  DispatchTabRemovedAndUnregisterNotifications(contents, tab_id,
+      tab_strip_model->closing_all());
 }
 
 void BrowserEventRouter::ActiveTabChanged(WebContents* old_contents,
@@ -478,6 +460,44 @@ BrowserEventRouter::TabEntry* BrowserEventRouter::GetTabEntry(
   return &i->second;
 }
 
+void BrowserEventRouter::DispatchTabDetached(WebContents* contents,
+      int index) {
+  scoped_ptr<ListValue> args(new ListValue());
+  args->Append(Value::CreateIntegerValue(ExtensionTabUtil::GetTabId(contents)));
+
+  DictionaryValue* object_args = new DictionaryValue();
+  object_args->Set(tab_keys::kOldWindowIdKey, Value::CreateIntegerValue(
+      ExtensionTabUtil::GetWindowIdOfTab(contents)));
+  object_args->Set(tab_keys::kOldPositionKey, Value::CreateIntegerValue(
+      index));
+  args->Append(object_args);
+
+  Profile* profile = Profile::FromBrowserContext(contents->GetBrowserContext());
+  DispatchEvent(profile, events::kOnTabDetached, args.Pass(),
+                EventRouter::USER_GESTURE_UNKNOWN);
+}
+
+void BrowserEventRouter::DispatchTabRemovedAndUnregisterNotifications(
+      WebContents* contents, int tab_id, bool window_closing) {
+  scoped_ptr<ListValue> args(new ListValue());
+  args->Append(Value::CreateIntegerValue(tab_id));
+
+  DictionaryValue* object_args = new DictionaryValue();
+  object_args->SetInteger(tab_keys::kWindowIdKey,
+                          ExtensionTabUtil::GetWindowIdOfTab(contents));
+  object_args->SetBoolean(tab_keys::kWindowClosing,
+                          window_closing);
+  args->Append(object_args);
+
+  Profile* profile = Profile::FromBrowserContext(contents->GetBrowserContext());
+  DispatchEvent(profile, events::kOnTabRemoved, args.Pass(),
+                EventRouter::USER_GESTURE_UNKNOWN);
+
+  int removed_count = tab_entries_.erase(tab_id);
+  DCHECK_GT(removed_count, 0);
+  UnregisterForTabNotifications(contents);
+}
+
 void BrowserEventRouter::Observe(int type,
                                  const content::NotificationSource& source,
                                  const content::NotificationDetails& details) {