linux: set auto-expand-level in ResourcesStatusDataProvider

Setting the auto-expand-level to 1 of the returned TmfTreeModel when
calling fetchTree() will indicate to the clients that only the top-level
should be expanded and their children supposed to be collapsed.

With this trace server clients can apply thhis and it fixes FE issue
eclipse-cdt-cloud/theia-trace-extension#801

Note: The classic Eclipse UI has been doing this in the UI code without
that setting (see ResourcesView).

Signed-off-by: Bernd Hufmann <[email protected]>

Author: bhufmann

analysis/org.eclipse.tracecompass.analysis.os.linux.core/src/org/eclipse/tracecompass/internal/analysis/os/linux/core/resourcesstatus/ResourcesStatusDataProvider.java

@@ -274,7 +274,11 @@ protected ResourcesStatusDataProvider(@NonNull ITmfTrace trace, @NonNull TmfStat
         }
         Collections.sort(builder, COMPARATOR);
 
-        return new TmfTreeModel<>(Collections.emptyList(), ImmutableList.copyOf(builder));
+        TmfTreeModel.Builder<@NonNull ResourcesEntryModel> treeModelBuilder = new TmfTreeModel.Builder<@NonNull ResourcesEntryModel>()
+                .setAutoExpandLevel(1) // only expand top level
+                .setEntries(ImmutableList.copyOf(builder));
+
+        return treeModelBuilder.build();
     }
 
     private static long getCpuFrequency(@NonNull ITmfStateSystem ss, int cpuQuark, @NonNull String freqAttribute) throws StateSystemDisposedException {