timeline: copy waveform when copying

app/widget/timelinewidget/tool/pointer.cpp

@@ -605,6 +605,9 @@ void PointerTool::FinishDrag(TimelineViewMouseEvent *event)
         // Duplicate rather than move
         // Place the copy instead of the original block
         block = static_cast<Block*>(Node::CopyNodeInGraph(block, command));
+        if (ClipBlock *new_clip = dynamic_cast<ClipBlock*>(block)) {
+          new_clip->waveform() = static_cast<ClipBlock*>(p.block)->waveform();
+        }
       }
 
       const Track::Reference& track_ref = p.ghost->GetAdjustedTrack();

app/widget/timelinewidget/undo/timelineundosplit.cpp

@@ -20,6 +20,7 @@
 
 #include "timelineundosplit.h"
 
+#include "node/block/clip/clip.h"
 #include "node/block/transition/transition.h"
 #include "widget/nodeview/nodeviewundo.h"
 
@@ -37,6 +38,10 @@ void BlockSplitCommand::redo()
   if (!reconnect_tree_command_) {
     reconnect_tree_command_ = new MultiUndoCommand();
     new_block_ = static_cast<Block*>(Node::CopyNodeInGraph(block_, reconnect_tree_command_));
+    if (ClipBlock *new_clip = dynamic_cast<ClipBlock*>(new_block_)) {
+      ClipBlock *old_clip = static_cast<ClipBlock*>(block_);
+      new_clip->waveform() = old_clip->waveform();
+    }
   }
 
   reconnect_tree_command_->redo_now();