Fix zip_root not being defined when importing by drag&drop

(cherry picked from commit 056deefa55fe90659ac3b13bde1b6df5f22c8aae)

editor/project_manager.cpp

@@ -103,7 +103,6 @@ private:
 	FileDialog *fdialog_install;
 	String zip_path;
 	String zip_title;
-	String zip_root;
 	AcceptDialog *dialog_error;
 	String fav_dir;
 
@@ -204,9 +203,7 @@ private:
 						char fname[16384];
 						ret = unzGetCurrentFileInfo(pkg, &info, fname, 16384, nullptr, 0, nullptr, 0);
 
-						String fname_str = String(fname);
-						if (fname_str.ends_with("project.godot")) {
-							zip_root = fname_str.substr(0, fname_str.rfind("project.godot"));
+						if (String(fname).ends_with("project.godot")) {
 							break;
 						}
 
@@ -508,7 +505,24 @@ private:
 						return;
 					}
 
+					// Find the zip_root
+					String zip_root;
 					int ret = unzGoToFirstFile(pkg);
+					while (ret == UNZ_OK) {
+						unz_file_info info;
+						char fname[16384];
+						unzGetCurrentFileInfo(pkg, &info, fname, 16384, nullptr, 0, nullptr, 0);
+
+						String name = fname;
+						if (name.ends_with("project.godot")) {
+							zip_root = name.substr(0, name.rfind("project.godot"));
+							break;
+						}
+
+						ret = unzGoToNextFile(pkg);
+					}
+
+					ret = unzGoToFirstFile(pkg);
 
 					Vector<String> failed_files;