various small fixes

libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/SWF.java

@@ -194,7 +194,7 @@ public final class SWF implements SWFContainerItem, Timelined {
     public List<Tag> tags = new ArrayList<>();
 
     @Internal
-    public boolean hasEndTag;
+    public boolean hasEndTag = true;
 
     /**
      * ExportRectangle for the display

libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/tags/DefineSpriteTag.java

@@ -313,18 +313,6 @@ public class DefineSpriteTag extends CharacterTag implements DrawableTag, Timeli
         return getTimeline().getFrameCount(); // frameCount
     }
 
-    private int getRealFrameCount() {
-        int cnt = 1;
-        Timeline timeline = getTimeline();
-        for (int i = 1; i < timeline.getFrameCount(); i++) {
-            if (timeline.getFrame(i).layersChanged) {
-                cnt++;
-            }
-        }
-
-        return cnt;
-    }
-
     @Override
     public boolean isSingleFrame() {
         if (!isSingleFrameInitialized) {
@@ -335,7 +323,7 @@ public class DefineSpriteTag extends CharacterTag implements DrawableTag, Timeli
 
     private synchronized void initialiteIsSingleFrame() {
         if (!isSingleFrameInitialized) {
-            if (getRealFrameCount() > 1) {
+            if (getTimeline().getRealFrameCount() > 1) {
                 isSingleFrameInitialized = true;
                 return;
             }

libsrc/ffdec_lib/src/com/jpexs/decompiler/flash/timeline/Timeline.java

@@ -159,6 +159,19 @@ public class Timeline {
         return frames.size();
     }
 
+    public int getRealFrameCount() {
+        ensureInitialized();
+
+        int cnt = 1;
+        for (int i = 1; i < frames.size(); i++) {
+            if (frames.get(i).layersChanged) {
+                cnt++;
+            }
+        }
+
+        return cnt;
+    }
+
     public int getFrameForAction(ASMSource asm) {
         Integer frame = actionFrames.get(asm);
         if (frame == null) {