Implement retry flow on DriveUploader.

chrome/browser/google_apis/gdata_wapi_operations.cc

Index: chrome/browser/google_apis/gdata_wapi_operations.cc
diff --git a/chrome/browser/google_apis/gdata_wapi_operations.cc b/chrome/browser/google_apis/gdata_wapi_operations.cc
index fef4be103131b3511f266325329888c55bdfe18d..a2e5124a3c8ab630be3de878afb2c6820093932f 100644
--- a/chrome/browser/google_apis/gdata_wapi_operations.cc
+++ b/chrome/browser/google_apis/gdata_wapi_operations.cc
@@ -88,6 +88,7 @@ ResumeUploadParams::ResumeUploadParams(
     int64 content_length,
     const std::string& content_type,
     scoped_refptr<net::IOBuffer> buf,
+    int64 buf_offset,
     const GURL& upload_location,
     const FilePath& drive_file_path) : upload_mode(upload_mode),
                                     start_position(start_position),
@@ -95,6 +96,7 @@ ResumeUploadParams::ResumeUploadParams(
                                     content_length(content_length),
                                     content_type(content_type),
                                     buf(buf),
+                                    buf_offset(buf_offset),
                                     upload_location(upload_location),
                                     drive_file_path(drive_file_path) {
 }
@@ -771,7 +773,7 @@ std::vector<std::string> ResumeUploadOperation::GetExtraRequestHeaders() const {
 bool ResumeUploadOperation::GetContentData(std::string* upload_content_type,
                                            std::string* upload_content) {
   *upload_content_type = params_.content_type;
-  *upload_content = std::string(params_.buf->data(),
+  *upload_content = std::string(params_.buf->data() + params_.buf_offset,
                                 params_.end_position - params_.start_position);
   return true;
 }