[Extensions Sync] Don't apply sync data for unsyncable extensions

chrome/browser/extensions/chrome_test_extension_loader.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/extensions/chrome_test_extension_loader.h"
 
 #include <memory>
 
 #include "base/files/file_util.h"
 #include "base/run_loop.h"
@@ skipping 86 matching lines @@
       .WaitForExtensionViewsToLoad();
 }
 
 base::FilePath ChromeTestExtensionLoader::PackExtension(
     const base::FilePath& unpacked_path) {
   if (!base::PathExists(unpacked_path)) {
     ADD_FAILURE() << "Unpacked path does not exist: " << unpacked_path.value();
     return base::FilePath();
   }
 
+  if (!temp_dir_.CreateUniqueTempDir()) {
+    ADD_FAILURE() << "Could not create unique temp dir.";
+    return base::FilePath();
+  }
   base::FilePath crx_path = temp_dir_.GetPath().AppendASCII("temp.crx");
   if (base::PathExists(crx_path)) {
     ADD_FAILURE() << "Crx path exists: " << crx_path.value()
         << ", are you trying to reuse the same ChromeTestExtensionLoader?";
     return base::FilePath();
   }
   base::FilePath fallback_pem_path =
       temp_dir_.GetPath().AppendASCII("temp.pem");
   if (base::PathExists(fallback_pem_path)) {
     ADD_FAILURE() << "PEM path exists: " << fallback_pem_path.value()
         << ", are you trying to reuse the same ChromeTestExtensionLoader?";
     return base::FilePath();
   }
 
-  base::FilePath* pem_path_to_use = &fallback_pem_path;
+  base::FilePath empty_path;
+  base::FilePath* pem_path_to_use = &empty_path;
   if (!pem_path_.empty()) {
     pem_path_to_use = &pem_path_;
     if (!base::PathExists(pem_path_)) {
       ADD_FAILURE() << "Provided PEM path does not exist: "
                     << pem_path_.value();
       return base::FilePath();
     }
   }
 
   ExtensionCreator creator;
@@ skipping 90 matching lines @@
 
   std::string install_warnings_message = "Unexpected warnings for extension:\n";
   for (const InstallWarning& warning : install_warnings)
     install_warnings_message += "  " + warning.message + "\n";
 
   ADD_FAILURE() << install_warnings_message;
   return false;
 }
 
 }  // namespace extensions