Adds OnClickCanceled callback to views::Button

ui/views/controls/button/custom_button.cc

Index: ui/views/controls/button/custom_button.cc
diff --git a/ui/views/controls/button/custom_button.cc b/ui/views/controls/button/custom_button.cc
index 7bab3b69e4a007ea44ba4d15264ad40d641df674..0984915ce4d9c7032032e372bd8370e2975f9ce0 100644
--- a/ui/views/controls/button/custom_button.cc
+++ b/ui/views/controls/button/custom_button.cc
@@ -128,15 +128,19 @@ const char* CustomButton::GetClassName() const {
 }
 
 bool CustomButton::OnMousePressed(const ui::MouseEvent& event) {
-  if (state_ != STATE_DISABLED) {
-    if (ShouldEnterPushedState(event) && HitTestPoint(event.location()))
-      SetState(STATE_PRESSED);
-    if (request_focus_on_press_)
-      RequestFocus();
-    if (IsTriggerableEvent(event) && notify_action_ == NOTIFY_ON_PRESS) {
+  if (state_ == STATE_DISABLED)
+    return true;
+  if (ShouldEnterPushedState(event) && HitTestPoint(event.location()))
+    SetState(STATE_PRESSED);
+  if (request_focus_on_press_)
+    RequestFocus();
+  if (notify_action_ == NOTIFY_ON_PRESS) {
+    if (IsTriggerableEvent(event)) {
       NotifyClick(event);
       // NOTE: We may be deleted at this point (by the listener's notification
       // handler).
+    } else {
+      NotifyMouseReleasedWithoutClick(event);

[sadrul, 2015/11/04 19:13:10]

This looks odd. Why should we do this on mouse-press?

Maybe call this OnClickCanceled() instead?

[varkha, 2015/11/04 20:18:23]

I thought we would want this notification to be sent here for symmetry meaning
that we are not expecting the click anymore and can unravel whatever pending
state we might have.
Totally agree with the name, thanks for suggesting it.

     }
   }
   return true;
@@ -155,18 +159,19 @@ bool CustomButton::OnMouseDragged(const ui::MouseEvent& event) {
 void CustomButton::OnMouseReleased(const ui::MouseEvent& event) {
   if (state_ == STATE_DISABLED)
     return;
-
   if (!HitTestPoint(event.location())) {
     SetState(STATE_NORMAL);
-    return;
-  }
-
-  SetState(STATE_HOVERED);
-  if (IsTriggerableEvent(event) && notify_action_ == NOTIFY_ON_RELEASE) {
-    NotifyClick(event);
-    // NOTE: We may be deleted at this point (by the listener's notification
-    // handler).
+  } else {
+    SetState(STATE_HOVERED);
+    if (IsTriggerableEvent(event) && notify_action_ == NOTIFY_ON_RELEASE) {
+      NotifyClick(event);
+      // NOTE: We may be deleted at this point (by the listener's notification
+      // handler).
+      return;
+    }
   }
+  if (notify_action_ == NOTIFY_ON_RELEASE)
+    NotifyMouseReleasedWithoutClick(event);
 }
 
 void CustomButton::OnMouseCaptureLost() {