Add request header on gdata operation for testing ETag match.

chrome/browser/chromeos/drive/drive_api_service.cc

Index: chrome/browser/chromeos/drive/drive_api_service.cc
diff --git a/chrome/browser/chromeos/drive/drive_api_service.cc b/chrome/browser/chromeos/drive/drive_api_service.cc
index 8bdfbf764276ab230edd2fa883b5c5c2d24e806e..eff2a4afb195b7595fcc73b79cba668d55848290 100644
--- a/chrome/browser/chromeos/drive/drive_api_service.cc
+++ b/chrome/browser/chromeos/drive/drive_api_service.cc
@@ -165,6 +165,7 @@ void DriveAPIService::DownloadDocument(
     const FilePath& local_cache_path,
     const GURL& document_url,
     DocumentExportFormat format,
+    const std::string& etag,
     const gdata::DownloadActionCallback& callback) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
@@ -176,6 +177,7 @@ void DriveAPIService::DownloadFile(
       const FilePath& virtual_path,
       const FilePath& local_cache_path,
       const GURL& document_url,
+      const std::string& etag,
       const gdata::DownloadActionCallback& download_action_callback,
       const gdata::GetContentCallback& get_content_callback) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
@@ -186,6 +188,7 @@ void DriveAPIService::DownloadFile(
 
 void DriveAPIService::DeleteDocument(
     const GURL& document_url,
+    const std::string& etag,
     const gdata::EntryActionCallback& callback) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));