IDEA-157597 Background image: when nothing is selected in the LocalChanges, the PreviewDiff pane doesn't get applied background

platform/diff-impl/src/com/intellij/diff/impl/DiffRequestProcessor.java

@@ -59,6 +59,7 @@ import com.intellij.openapi.wm.ex.IdeFocusTraversalPolicy;
 import com.intellij.ui.HintHint;
 import com.intellij.ui.JBProgressBar;
 import com.intellij.ui.LightweightHint;
+import com.intellij.ui.components.JBPanelWithEmptyText;
 import com.intellij.ui.components.panels.Wrapper;
 import com.intellij.util.containers.ContainerUtil;
 import com.intellij.util.ui.JBUI;
@@ -815,7 +816,7 @@ public abstract class DiffRequestProcessor implements Disposable {
   // Helpers
   //
 
-  private class MyPanel extends JPanel implements DataProvider {
+  private class MyPanel extends JBPanelWithEmptyText implements DataProvider {
     public MyPanel() {
       super(new BorderLayout());
     }

platform/platform-api/src/com/intellij/ui/components/JBPanelWithEmptyText.java

@@ -35,6 +35,14 @@ public class JBPanelWithEmptyText extends JBPanel<JBPanelWithEmptyText> implemen
     }
   };
 
+  public JBPanelWithEmptyText() {
+    super();
+  }
+
+  public JBPanelWithEmptyText(LayoutManager layout) {
+    super(layout);
+  }
+
   @NotNull
   @Override
   public StatusText getEmptyText() {