Send mouse events for disabled form controls.

third_party/WebKit/Source/core/events/MouseEvent.cpp

Index: third_party/WebKit/Source/core/events/MouseEvent.cpp
diff --git a/third_party/WebKit/Source/core/events/MouseEvent.cpp b/third_party/WebKit/Source/core/events/MouseEvent.cpp
index ae1da564be060c79e755b2e07b32b77cddc9a3e5..e5c12ba5b42af861a63276341235636918b9dc90 100644
--- a/third_party/WebKit/Source/core/events/MouseEvent.cpp
+++ b/third_party/WebKit/Source/core/events/MouseEvent.cpp
@@ -439,10 +439,19 @@ DispatchEventResult MouseEventDispatchMediator::DispatchEvent(
   mouse_event.GetEventPath().AdjustForRelatedTarget(
       dispatcher.GetNode(), mouse_event.relatedTarget());
 
+  bool is_click = mouse_event.type() == EventTypeNames::click;
+  bool send_to_disabled_forms =

[jbroman, 2017/04/24 18:19:49]

super-nit: send_to_disabled_controls or something like that? This made me think
it applied to forms as a whole being disabled.

[dtapuska, 2017/04/24 19:14:39]

Done.

+      RuntimeEnabledFeatures::sendMouseEventsDisabledFormControlsEnabled();
+
+  if (send_to_disabled_forms && is_click &&
+      mouse_event.GetEventPath().DisabledFormControlExistsInPath()) {
+    return DispatchEventResult::kCanceledBeforeDispatch;
+  }
+
   if (!mouse_event.isTrusted())

[jbroman, 2017/04/24 18:19:49]

Does the layout test cover the logic beyond this point? It was my understanding
that "new MouseEvent" creates a non-trusted event.

[dtapuska, 2017/04/24 19:14:39]

Yes that is correct. But the changed logic is *before* this conditional. The
logic *after* this event check is the legacy path.

     return dispatcher.Dispatch();
 
-  if (IsDisabledFormControl(&dispatcher.GetNode()))
+  if (!send_to_disabled_forms && IsDisabledFormControl(&dispatcher.GetNode()))
     return DispatchEventResult::kCanceledBeforeDispatch;
 
   if (mouse_event.type().IsEmpty())
@@ -455,7 +464,7 @@ DispatchEventResult MouseEventDispatchMediator::DispatchEvent(
 
   DispatchEventResult dispatch_result = dispatcher.Dispatch();
 
-  if (mouse_event.type() != EventTypeNames::click || mouse_event.detail() != 2)
+  if (!is_click || mouse_event.detail() != 2)
     return dispatch_result;
 
   // Special case: If it's a double click event, we also send the dblclick