Support an --install-from-webstore command line switch

chrome/browser/extensions/crx_installer.cc

 // Copyright (c) 2012 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/crx_installer.h"
 
 #include <map>
 #include <set>
 
 #include "base/bind.h"
@@ skipping 88 matching lines @@
       allow_silent_install_(false),
       install_cause_(extension_misc::INSTALL_CAUSE_UNSET),
       creation_flags_(Extension::NO_FLAGS),
       off_store_install_allow_reason_(OffStoreInstallDisallowed),
       did_handle_successfully_(true),
       record_oauth2_grant_(false) {
   if (!approval)
     return;
 
   CHECK(profile_->IsSameProfile(approval->profile));
-  client_->install_ui()->SetUseAppInstalledBubble(
-      approval->use_app_installed_bubble);
-  client_->install_ui()->SetSkipPostInstallUI(approval->skip_post_install_ui);
+  if (client_) {
+    client_->install_ui()->SetUseAppInstalledBubble(
+        approval->use_app_installed_bubble);
+    client_->install_ui()->SetSkipPostInstallUI(approval->skip_post_install_ui);
+  }
 
   if (approval->skip_install_dialog) {
     // Mark the extension as approved, but save the expected manifest and ID
     // so we can check that they match the CRX's.
     approved_ = true;
     expected_manifest_.reset(approval->parsed_manifest->DeepCopy());
     expected_id_ = approval->extension_id;
     record_oauth2_grant_ = approval->record_oauth2_grant;
   }
 }
 
 CrxInstaller::~CrxInstaller() {
   // Delete the temp directory and crx file as necessary. Note that the
   // destructor might be called on any thread, so we post a task to the file
   // thread to make sure the delete happens there. This is a best effort
   // operation since the browser can be shutting down so there might not
   // be a file thread to post to.
   if (!temp_dir_.value().empty()) {
     BrowserThread::PostTask(BrowserThread::FILE, FROM_HERE,
         base::Bind(&extension_file_util::DeleteFile, temp_dir_, true));
   }
   if (delete_source_) {
     BrowserThread::PostTask(BrowserThread::FILE, FROM_HERE,
         base::Bind(&extension_file_util::DeleteFile, source_file_, false));
   }
   // Make sure the UI is deleted on the ui thread.
-  BrowserThread::DeleteSoon(BrowserThread::UI, FROM_HERE, client_);
-  client_ = NULL;
+  if (client_) {
+    BrowserThread::DeleteSoon(BrowserThread::UI, FROM_HERE, client_);
+    client_ = NULL;
+  }
 }
 
 void CrxInstaller::InstallCrx(const FilePath& source_file) {
   source_file_ = source_file;
 
   scoped_refptr<SandboxedUnpacker> unpacker(
       new SandboxedUnpacker(
           source_file,
           content::ResourceDispatcherHost::Get() != NULL,
           install_source_,
@@ skipping 465 matching lines @@
   // is problematic because they don't know anything about the
   // extension before it is unpacked, so they cannot filter based
   // on the extension.
   content::NotificationService::current()->Notify(
       chrome::NOTIFICATION_CRX_INSTALLER_DONE,
       content::Source<CrxInstaller>(this),
       content::Details<const Extension>(extension));
 }
 
 }  // namespace extensions