【工具栏】搜索，缺少搜索历史 修复

PDF Office/PDF Master/Class/PDFTools/FindSearch/KMSearchFindView.swift

@@ -36,7 +36,12 @@ class KMSearchFindView: KMBaseXibView {
     }
 
     private func refreshSearchBarMenu() {
-        let words = UserDefaults.standard.object(forKey: "kmDocumentSearchWordArrays") as? [String] ?? []
+        var words = UserDefaults.standard.object(forKey: "kmDocumentSearchWordArrays") as? [String]
+        if words == nil {
+            UserDefaults.standard.setValue([], forKey: "kmDocumentSearchWordArrays")
+            words = []
+        }
+        guard let words = words else { return }
         let searchMenu = NSMenu()
 
         for word in words {