[InputEvent] Support |deleteByDrag|, |insertFromDrop| and fire in sequential order

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

Index: third_party/WebKit/Source/core/editing/commands/CompositeEditCommand.h
diff --git a/third_party/WebKit/Source/core/editing/commands/CompositeEditCommand.h b/third_party/WebKit/Source/core/editing/commands/CompositeEditCommand.h
index e96d8a2bae37f8c20ebbba8669688b5aab041509..b09d18a3a08b8c3ca08c6575a248d235627680b3 100644
--- a/third_party/WebKit/Source/core/editing/commands/CompositeEditCommand.h
+++ b/third_party/WebKit/Source/core/editing/commands/CompositeEditCommand.h
@@ -51,6 +51,7 @@ public:
     void reapply() override;
     InputEvent::InputType inputType() const override;
     void append(SimpleEditCommand*);
+    void append(EditCommandComposition*);
 
     const VisibleSelection& startingSelection() const { return m_startingSelection; }
     const VisibleSelection& endingSelection() const { return m_endingSelection; }
@@ -85,6 +86,8 @@ public:
     bool isFirstCommand(EditCommand* command) { return !m_commands.isEmpty() && m_commands.first() == command; }
     EditCommandComposition* composition() { return m_composition.get(); }
     EditCommandComposition* ensureComposition();
+    // Append composition from an already applied command.
+    void appendCommandToComposite(CompositeEditCommand*);
 
     virtual bool isReplaceSelectionCommand() const;
     virtual bool isTypingCommand() const;