Change default Omaha installsource param from "" to "ondemand"

chrome/browser/extensions/webstore_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/webstore_installer.h"
 
 #include "base/basictypes.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/file_util.h"
@@ skipping 48 matching lines @@
 const char kApprovalKey[] = "extensions.webstore_installer";
 
 const char kInvalidIdError[] = "Invalid id";
 const char kNoBrowserError[] = "No browser found";
 const char kDownloadDirectoryError[] = "Could not create download directory";
 const char kDownloadCanceledError[] = "Download canceled";
 const char kInstallCanceledError[] = "Install canceled";
 const char kDownloadInterruptedError[] = "Download interrupted";
 const char kInvalidDownloadError[] = "Download was not a CRX";
 const char kInlineInstallSource[] = "inline";
-const char kDefaultInstallSource[] = "";
+const char kDefaultInstallSource[] = "ondemand";
 
 base::FilePath* g_download_directory_for_tests = NULL;
 
 // Must be executed on the FILE thread.
 void GetDownloadFilePath(
     const base::FilePath& download_directory, const std::string& id,
     const base::Callback<void(const base::FilePath&)>& callback) {
   base::FilePath directory(g_download_directory_for_tests ?
                      *g_download_directory_for_tests : download_directory);
 
@@ skipping 348 matching lines @@
 void WebstoreInstaller::ReportSuccess() {
   if (delegate_) {
     delegate_->OnExtensionInstallSuccess(id_);
     delegate_ = NULL;
   }
 
   Release();  // Balanced in Start().
 }
 
 }  // namespace extensions