X11: Remove calls to XSelectInput

ui/base/x/x11_window_event_manager.cc

Index: ui/base/x/x11_window_event_manager.cc
diff --git a/ui/base/x/x11_window_event_manager.cc b/ui/base/x/x11_window_event_manager.cc
index 4fc0c559772acd478825f3890bb65ffefa05f3c1..78fd14ac4b3241498e651882b693972c05ce5db9 100644
--- a/ui/base/x/x11_window_event_manager.cc
+++ b/ui/base/x/x11_window_event_manager.cc
@@ -1,4 +1,4 @@
-// Copyright 2014 The Chromium Authors. All rights reserved.
+// Copyright 2016 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.
 
@@ -9,18 +9,21 @@
 #include <X11/Xlib-xcb.h>
 #include <xcb/xcb.h>
 
-#include "base/compiler_specific.h"
 #include "base/memory/singleton.h"
 
 namespace ui {
 
 XScopedEventSelector::XScopedEventSelector(XID xid, uint32_t event_mask)
-    : xid_(xid), event_mask_(event_mask) {
-  XWindowEventManager::GetInstance()->SelectEvents(xid_, event_mask_);
+    : xid_(xid),
+      event_mask_(event_mask),
+      event_manager_(
+          XWindowEventManager::GetInstance()->weak_ptr_factory_.GetWeakPtr()) {
+  event_manager_->SelectEvents(xid_, event_mask_);
 }
 
 XScopedEventSelector::~XScopedEventSelector() {
-  XWindowEventManager::GetInstance()->DeselectEvents(xid_, event_mask_);
+  if (event_manager_)
+    event_manager_->DeselectEvents(xid_, event_mask_);
 }
 
 // static
@@ -70,8 +73,12 @@ class XWindowEventManager::MultiMask {
   DISALLOW_COPY_AND_ASSIGN(MultiMask);
 };
 
-XWindowEventManager::XWindowEventManager() {}
-XWindowEventManager::~XWindowEventManager() {}
+XWindowEventManager::XWindowEventManager() : weak_ptr_factory_(this) {}
+
+XWindowEventManager::~XWindowEventManager() {
+  for (const auto& mask_pair : mask_map_)

[Daniel Erat, 2016/09/14 04:56:09]

i'd recommend adding a comment here like:

  // Clear events still requested by not-yet-deleted XScopedEventSelectors.

[Tom (Use chromium acct), 2016/09/14 17:51:08]

Done.

+    ChangeEventMask(mask_pair.first, NoEventMask);
+}
 
 void XWindowEventManager::SelectEvents(XID xid, uint32_t event_mask) {
   std::unique_ptr<MultiMask>& mask = mask_map_[xid];
@@ -95,6 +102,13 @@ void XWindowEventManager::AfterMaskChanged(XID xid, uint32_t old_mask) {
   if (new_mask == old_mask)
     return;
 
+  ChangeEventMask(xid, new_mask);
+
+  if (new_mask == NoEventMask)
+    mask_map_.erase(xid);
+}
+
+void XWindowEventManager::ChangeEventMask(XID xid, uint32_t new_mask) {
   XDisplay* display = gfx::GetXDisplay();
   xcb_connection_t* connection = XGetXCBConnection(display);
   auto cookie = xcb_change_window_attributes(connection, xid, XCB_CW_EVENT_MASK,
@@ -103,9 +117,6 @@ void XWindowEventManager::AfterMaskChanged(XID xid, uint32_t old_mask) {
   // change_attributes request may give a BadWindow error.  In this case, just
   // ignore the error.
   xcb_discard_reply(connection, cookie.sequence);
-
-  if (new_mask == NoEventMask)
-    mask_map_.erase(xid);
 }
 
 }  // namespace ui