Clip: Remove unused isChild method

src/Media/Clip.cpp

@@ -252,20 +252,6 @@ Clip::clear()
     m_subclips.clear();
 }
 
-bool
-Clip::isChild( const QUuid &uuid) const
-{
-    Clip*   c = m_parent;
-
-    while ( c != nullptr )
-    {
-        if ( c->m_uuid == uuid )
-            return true;
-        c = c->m_parent;
-    }
-    return false;
-}
-
 QVariant
 Clip::toVariant() const
 {

src/Media/Clip.h

@@ -130,11 +130,6 @@ class   Clip : public Workflow::Helper
 
         bool                addSubclip( Clip* clip );
 
-        /**
-         *  \return         true if the clip is a child of the given clip uuid
-         */
-        bool                isChild( const QUuid& uuid ) const;
-
         QVariant            toVariant() const;
         QVariant            toVariantFull() const;