Move methods according to their responsibilities

src/client/js/services/PageContainer.js

@@ -632,17 +632,4 @@ export default class PageContainer extends Container {
   retrieveMyBookmarkList() {
   }
 
-  get compareRevisionIds() {
-    const searchParams = {};
-    for (const param of window.location.search?.substr(1)?.split('&')) {
-      const [k,v] = param.split('=');
-      searchParams[k] = v;
-    }
-    if (!searchParams['compare']) {
-      return [];
-    }
-
-    return searchParams['compare'].split('...') || [];
-  }
-
 }

src/client/js/services/RevisionCompareContainer.js

@@ -147,4 +147,17 @@ export default class RevisionCompareContainer extends Container {
     this.setState({ toRevision: revision });
   }
 
+  get compareRevisionIds() {
+    const searchParams = {};
+    for (const param of window.location.search?.substr(1)?.split('&')) {
+      const [k,v] = param.split('=');
+      searchParams[k] = v;
+    }
+    if (!searchParams['compare']) {
+      return [];
+    }
+
+    return searchParams['compare'].split('...') || [];
+  }
+
 }