Do not block all task manager tree view mouse release events....

chrome/browser/gtk/task_manager_gtk.cc

Index: chrome/browser/gtk/task_manager_gtk.cc
===================================================================
--- chrome/browser/gtk/task_manager_gtk.cc	(revision 20927)
+++ chrome/browser/gtk/task_manager_gtk.cc	(working copy)
@@ -341,8 +341,6 @@
                                GTK_TREE_VIEW_GRID_LINES_HORIZONTAL);
   g_signal_connect(G_OBJECT(treeview_), "button-press-event",
                    G_CALLBACK(OnButtonPressEvent), this);
-  g_signal_connect(G_OBJECT(treeview_), "button-release-event",
-                   G_CALLBACK(OnButtonReleaseEvent), this);
   gtk_widget_add_events(treeview_,
                         GDK_BUTTON_PRESS_MASK | GDK_BUTTON_RELEASE_MASK);
 
@@ -553,9 +551,8 @@
 gboolean TaskManagerGtk::OnButtonReleaseEvent(GtkWidget* widget,
                                               GdkEventButton* event,
                                               TaskManagerGtk* task_manager) {
-  // We don't want to open the context menu in the treeview.
-  if (widget == task_manager->treeview_)
-    return TRUE;
+  if (gtk_util::WidgetContainsCursor(task_manager->treeview_))
+    return FALSE;
 
   if (event->button == 3)
     task_manager->ShowContextMenu();