Update the CrxInstaller and UnpackedInstaller to use the ExtensionInstallChecker

chrome/browser/extensions/extension_install_checker.cc

 // Copyright 2014 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/extension_install_checker.h"
 
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/extensions/blacklist.h"
 #include "chrome/browser/extensions/requirements_checker.h"
 #include "chrome/browser/profiles/profile.h"
@@ skipping 145 matching lines @@
     failed_mask |= CHECK_MANAGEMENT_POLICY;
 
   // Invoke callback if all checks are complete or there was at least one
   // failure and |fail_fast_| is true.
   if (!is_running() || (failed_mask && fail_fast_)) {
     // If we are failing fast, discard any pending results.
     weak_ptr_factory_.InvalidateWeakPtrs();
     running_checks_ = 0;
     ++current_sequence_number_;
 
-    callback_.Run(failed_mask);
+    Callback callback_copy = callback_;
     callback_.Reset();
+
+    // This instance may be owned by the callback recipient and deleted here,
+    // so reset |callback_| first and invoke a copy of the callback.
+    callback_copy.Run(failed_mask);
   }
 }
 
 }  // namespace extensions