2nd try: Support synchronous mode in WebFileWriterImpl

content/child/fileapi/webfilesystem_impl.cc

Index: content/child/fileapi/webfilesystem_impl.cc
diff --git a/content/child/fileapi/webfilesystem_impl.cc b/content/child/fileapi/webfilesystem_impl.cc
index 78952b57c702da9d081ef85e2f57f190a42052f2..052bce489c929cdec5ea9746d026648ff83fff42 100644
--- a/content/child/fileapi/webfilesystem_impl.cc
+++ b/content/child/fileapi/webfilesystem_impl.cc
@@ -252,8 +252,11 @@ void DidCreateFileWriter(
     callbacks->didFail(WebKit::WebFileErrorInvalidState);
     return;
   }
+  WebFileWriterImpl::Type type = callbacks->shouldBlockUntilCompletion() ?
+      WebFileWriterImpl::TYPE_SYNC : WebFileWriterImpl::TYPE_ASYNC;
   callbacks->didCreateFileWriter(
-      new WebFileWriterImpl(path, client, main_thread_loop), file_info.size);
+      new WebFileWriterImpl(path, client, type, main_thread_loop),
+      file_info.size);
 }
 
 void CreateFileWriterCallbackAdapter(
@@ -488,7 +491,9 @@ base::Unretained(waitable_results))),
 
 WebKit::WebFileWriter* WebFileSystemImpl::createFileWriter(
     const WebURL& path, WebKit::WebFileWriterClient* client) {
-  return new WebFileWriterImpl(GURL(path), client, main_thread_loop_.get());
+  return new WebFileWriterImpl(GURL(path), client,
+                               WebFileWriterImpl::TYPE_ASYNC,
+                               main_thread_loop_.get());
 }
 
 void WebFileSystemImpl::createFileWriter(