[coverage] API cleanup: remove unused deprecated API scheduled for removal (IJPL-178044)

GitOrigin-RevId: 6ca8b29096697f40ee98b88830f2561b74b104ca

plugins/coverage-common/api-dump.txt

@@ -293,7 +293,6 @@ a:com.intellij.coverage.view.CoverageViewExtension
 - canSelectInCoverageView(java.lang.Object):Z
 - a:createColumnInfos():com.intellij.util.ui.ColumnInfo[]
 - a:createRootNode():com.intellij.ide.util.treeView.AbstractTreeNode
-- createTopLevelNodes():java.util.List
 - a:getChildrenNodes(com.intellij.ide.util.treeView.AbstractTreeNode):java.util.List
 - getElementsCapitalisedName():java.lang.String
 - getElementsName():java.lang.String

plugins/coverage-common/src/com/intellij/coverage/view/CoverageViewExtension.java

@@ -113,15 +113,6 @@ public abstract class CoverageViewExtension {
     return CoverageBundle.message("coverage.files.capitalised");
   }
 
-  /**
-   * @deprecated This method is not used in CoverageView.
-   * The root node should return a correct list of children instead.
-   */
-  @Deprecated(forRemoval = true)
-  public @NotNull List<AbstractTreeNode<?>> createTopLevelNodes() {
-    return Collections.emptyList();
-  }
-
   /**
    * @deprecated This method is not used in CoverageView.
    */