Let SvgViewManager handle removing node and view references.

android/src/main/java/com/horcrux/svg/SvgView.java

@@ -78,12 +78,6 @@ public class SvgView extends ViewGroup {
         SvgViewManager.setSvgView(this);
     }
 
-    @Override
-    protected void onDetachedFromWindow() {
-        super.onDetachedFromWindow();
-        SvgViewManager.dropSvgView(this);
-    }
-
     @Override
     public void invalidate() {
         super.invalidate();
@@ -97,7 +91,11 @@ public class SvgView extends ViewGroup {
     protected void onDraw(Canvas canvas) {
         super.onDraw(canvas);
         if (mBitmap == null) {
-            mBitmap = getShadowNode().drawOutput();
+            SvgViewShadowNode node = getShadowNode();
+            if (node == null) {
+                return;
+            }
+            mBitmap = node.drawOutput();
         }
         canvas.drawBitmap(mBitmap, 0, 0, null);
     }

android/src/main/java/com/horcrux/svg/SvgViewManager.java

@@ -50,12 +50,6 @@ class SvgViewManager extends ViewGroupManager<SvgView> {
         mTagToSvgView.put(svg.getId(), svg);
     }
 
-    static void dropSvgView(SvgView view) {
-        int tag = view.getId();
-        mTagToShadowNode.remove(tag);
-        mTagToSvgView.remove(tag);
-    }
-
     @SuppressWarnings("unused")
     static @Nullable SvgView getSvgViewByTag(int tag) {
         return mTagToSvgView.get(tag);
@@ -92,4 +86,12 @@ class SvgViewManager extends ViewGroupManager<SvgView> {
         root.invalidate();
     }
 
+    @Override
+    public void onDropViewInstance(SvgView view) {
+        super.onDropViewInstance(view);
+
+        int tag = view.getId();
+        mTagToShadowNode.remove(tag);
+        mTagToSvgView.remove(tag);
+    }
 }