[unpacker] Allow only one ZIP handler at once: either the new or the old one.

chrome/browser/chromeos/file_manager/file_tasks.cc

Index: chrome/browser/chromeos/file_manager/file_tasks.cc
diff --git a/chrome/browser/chromeos/file_manager/file_tasks.cc b/chrome/browser/chromeos/file_manager/file_tasks.cc
index 238a29eee0f59909d9e97c557d354d8497e98ef5..518737220049b83271ac7a355b99a3fdb226bb84 100644
--- a/chrome/browser/chromeos/file_manager/file_tasks.cc
+++ b/chrome/browser/chromeos/file_manager/file_tasks.cc
@@ -26,6 +26,7 @@
 #include "chrome/common/extensions/api/file_manager_private.h"
 #include "chrome/common/extensions/extension_constants.h"
 #include "chrome/common/pref_names.h"
+#include "chromeos/chromeos_switches.h"
 #include "extensions/browser/extension_host.h"
 #include "extensions/browser/extension_registry.h"
 #include "extensions/browser/extension_system.h"
@@ -391,6 +392,14 @@ void FindFileHandlerTasks(
     if (file_handlers.empty())
       continue;
 
+    // If the new ZIP unpacker is disabled, then hide its handlers, so we don't
+    // show both the legacy one and the new one in Files app for ZIP files.
+    if (extension->id() == extension_misc::kZIPUnpackerExtensionId &&
+        CommandLine::ForCurrentProcess()->HasSwitch(
+            chromeos::switches::kDisableNewZIPUnpacker)) {
+      continue;
+    }
+
     // Only show the first matching handler from each app.
     const extensions::FileHandlerInfo* file_handler = file_handlers.front();
     std::string task_id = file_tasks::MakeTaskID(