MapWithAILayerInfo: Reduce initial allocations

For this, we just avoid saving preferences until we are are't getting
all the data sources.

For most users, this should have no effect. Only users that open JOSM,
quickly make a preference change, and exit without the preference.save
method being called will have issues.

Signed-off-by: Taylor Smock <tsmock@fb.com>

src/main/java/org/openstreetmap/josm/plugins/mapwithai/data/mapwithai/MapWithAILayerInfo.java

@@ -24,6 +24,7 @@ import javax.annotation.Nonnull;
 import javax.swing.SwingUtilities;
 
 import org.openstreetmap.josm.actions.ExpertToggleAction;
+import org.openstreetmap.josm.data.Preferences;
 import org.openstreetmap.josm.data.StructUtils;
 import org.openstreetmap.josm.data.imagery.ImageryInfo;
 import org.openstreetmap.josm.data.preferences.BooleanProperty;
@@ -270,11 +271,34 @@ public class MapWithAILayerInfo {
             if (this.clearCache) {
                 ESRISourceReader.SOURCE_CACHE.clear();
             }
-            for (String source : getImageryLayersSites()) {
-                if (canceled) {
-                    return;
+            // This is literally to avoid allocations on startup
+            final Preferences preferences;
+            if (Config.getPref() instanceof Preferences) {
+                preferences = (Preferences) Config.getPref();
+            } else {
+                preferences = null;
+            }
+            try {
+                if (preferences != null) {
+                    preferences.enableSaveOnPut(false);
+                }
+                for (String source : getImageryLayersSites()) {
+                    if (canceled) {
+                        return;
+                    }
+                    loadSource(source);
+                }
+            } finally {
+                if (preferences != null) {
+                    // saveOnPut is pretty much always true
+                    preferences.enableSaveOnPut(true);
+                    try {
+                        preferences.save();
+                    } catch (IOException e) {
+                        // This is highly unlikely to happen
+                        Logging.error(e);
+                    }
                 }
-                loadSource(source);
             }
             this.finish();
         }