[InputEvent] Update EndingSelection when appending UndoStep

third_party/WebKit/Source/core/editing/commands/CompositeEditCommand.cpp

 /*
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  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
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@@ skipping 198 matching lines @@
     command->SetEndingVisibleSelection(selection);
   }
   command->DoApply(editing_state);
   if (!editing_state->IsAborted())
     commands_.push_back(command);
 }
 
 void CompositeEditCommand::AppendCommandToUndoStep(
     CompositeEditCommand* command) {
   EnsureUndoStep()->Append(command->EnsureUndoStep());
+  EnsureUndoStep()->SetEndingSelection(

[yosin_UTC9, 2017/05/08 04:01:05]

Could you move |SetEndingSelection()| call to |Editor::AppliedEditing()| after
|AppendCommandToUndoStep()|?
To make |AppendCommandToUndoStep()| does just appending?
I'm not sure whether |AppendCommandToUndoStep()| should update ending selection
or not.
I would like to postpone the decision until we have another call site.

[chongz, 2017/05/08 23:37:53]

Moved to |Editor::AppliedEditing()| but I have to call |SetEndingSelection()|
before |AppendCommandToUndoStep()|.
e.g. |command->undo_step_| will be cleared during |AppendCommandToUndoStep()|.

+      command->EnsureUndoStep()->EndingSelection());
   command->undo_step_ = nullptr;
   command->SetParent(this);
   commands_.push_back(command);
 }
 
 void CompositeEditCommand::ApplyStyle(const EditingStyle* style,
                                       EditingState* editing_state) {
   ApplyCommandToComposite(
       ApplyStyleCommand::Create(GetDocument(), style,
                                 InputEvent::InputType::kNone),
@@ skipping 1743 matching lines @@
 
 DEFINE_TRACE(CompositeEditCommand) {
   visitor->Trace(commands_);
   visitor->Trace(starting_selection_);
   visitor->Trace(ending_selection_);
   visitor->Trace(undo_step_);
   EditCommand::Trace(visitor);
 }
 
 }  // namespace blink