Devtools[LayoutEditor]: Rework layout-editor workflow

Source/core/inspector/InspectorOverlayHost.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 33 matching lines @@
         return adoptRefWillBeNoop(new InspectorOverlayHost());
     }
     ~InspectorOverlayHost();
     DECLARE_TRACE();
 
     void resume();
     void stepOver();
     void startPropertyChange(const String&);
     void changeProperty(float delta);
     void endPropertyChange();
+    void clearSelection(bool commitChanges);
 
     class DebuggerListener : public WillBeGarbageCollectedMixin {
     public:
         virtual ~DebuggerListener() { }
         virtual void overlayResumed() = 0;
         virtual void overlaySteppedOver() = 0;
     };
     void setDebuggerListener(DebuggerListener* listener) { m_debuggerListener = listener; }
 
     class CORE_EXPORT LayoutEditorListener : public WillBeGarbageCollectedMixin {
     public:
         virtual ~LayoutEditorListener() { }
         virtual void overlayStartedPropertyChange(const String&) = 0;
         virtual void overlayPropertyChanged(float cssDelta) = 0;
         virtual void overlayEndedPropertyChange() = 0;
+        virtual void clearSelection(bool commitChanges) = 0;
     };
     void setLayoutEditorListener(LayoutEditorListener* listener) { m_layoutEditorListener = listener; }
 
 private:
     InspectorOverlayHost();
 
     RawPtrWillBeMember<DebuggerListener> m_debuggerListener;
     RawPtrWillBeMember<LayoutEditorListener> m_layoutEditorListener;
 
 };
 
 } // namespace blink
 
 #endif // InspectorOverlayHost_h