EditorEx: permanent header API

platform/lang-impl/src/com/intellij/injected/editor/EditorWindow.java

@@ -298,6 +298,16 @@ public class EditorWindow extends UserDataHolderBase implements EditorEx {
     return highlighter;
   }
 
+  @Override
+  public JComponent getPermanentHeaderComponent() {
+    return myDelegate.getPermanentHeaderComponent();
+  }
+
+  @Override
+  public void setPermanentHeaderComponent(JComponent component) {
+    myDelegate.setPermanentHeaderComponent(component);
+  }
+
   @Override
   @NotNull
   public JComponent getContentComponent() {

platform/platform-impl/src/com/intellij/openapi/editor/ex/EditorEx.java

@@ -57,6 +57,10 @@ public interface EditorEx extends Editor {
 
   EditorHighlighter getHighlighter();
 
+  JComponent getPermanentHeaderComponent();
+
+  void setPermanentHeaderComponent(JComponent component);
+
   void setHighlighter(@NotNull EditorHighlighter highlighter);
 
   void setColorsScheme(@NotNull EditorColorsScheme scheme);

platform/platform-impl/src/com/intellij/openapi/editor/impl/EditorImpl.java

@@ -1930,7 +1930,7 @@ public final class EditorImpl extends UserDataHolderBase implements EditorEx, Hi
   @Override
   public void setHeaderComponent(JComponent header) {
     myHeaderPanel.removeAll();
-    header = header == null ? getUserData(PERMANENT_HEADER) : header;
+    header = header == null ? getPermanentHeaderComponent() : header;
     if (header != null) {
       myHeaderPanel.add(header);
     }
@@ -1940,13 +1940,23 @@ public final class EditorImpl extends UserDataHolderBase implements EditorEx, Hi
 
   @Override
   public boolean hasHeaderComponent() {
-    return myHeaderPanel.getComponentCount() > 0;
+    JComponent header = getHeaderComponent();
+    return header != null && header != getPermanentHeaderComponent();
+  }
+
+  @Nullable
+  public JComponent getPermanentHeaderComponent() {
+    return getUserData(PERMANENT_HEADER);
+  }
+
+  public void setPermanentHeaderComponent(@Nullable JComponent component) {
+    putUserData(PERMANENT_HEADER, component);
   }
 
   @Override
   @Nullable
   public JComponent getHeaderComponent() {
-    if (hasHeaderComponent()) {
+    if (myHeaderPanel.getComponentCount() > 0) {
       return (JComponent)myHeaderPanel.getComponent(0);
     }
     return null;