Implement polling part of DriveFileSyncService

chrome/browser/google_apis/gdata_wapi_parser.cc

Index: chrome/browser/google_apis/gdata_wapi_parser.cc
diff --git a/chrome/browser/google_apis/gdata_wapi_parser.cc b/chrome/browser/google_apis/gdata_wapi_parser.cc
index ccf6edcf7772e12341b24b175fb0da25ba6acf69..c6f649f45e582007831a48381a5b1898ccfc3b95 100644
--- a/chrome/browser/google_apis/gdata_wapi_parser.cc
+++ b/chrome/browser/google_apis/gdata_wapi_parser.cc
@@ -68,6 +68,7 @@ const char kWritersCanInviteNode[] = "writersCanInvite";
 // Field names.
 const char kAuthorField[] = "author";
 const char kCategoryField[] = "category";
+const char kChangestampField[] = "docs$changestamp.value";
 const char kContentField[] = "content";
 const char kDeletedField[] = "gd$deleted";
 const char kETagField[] = "gd$etag";
@@ -593,7 +594,8 @@ DocumentEntry::DocumentEntry()
     : kind_(ENTRY_KIND_UNKNOWN),
       file_size_(0),
       deleted_(false),
-      removed_(false) {
+      removed_(false),
+      changestamp_(0) {
 }
 
 DocumentEntry::~DocumentEntry() {
@@ -605,6 +607,22 @@ bool DocumentEntry::HasFieldPresent(const base::Value* value,
   return true;
 }
 
+bool DocumentEntry::ParseChangestamp(const base::Value* value,
+                                     int64* result) {
+  DCHECK(result);
+  if (!value) {
+    *result = 0;
+    return true;
+  }
+
+  std::string string_value;
+  if (value->GetAsString(&string_value) &&
+      base::StringToInt64(string_value, result))
+    return true;
+
+  return false;
+}
+
 // static
 void DocumentEntry::RegisterJSONConverter(
     base::JSONValueConverter<DocumentEntry>* converter) {
@@ -640,6 +658,9 @@ void DocumentEntry::RegisterJSONConverter(
       kDeletedField, &DocumentEntry::deleted_, &DocumentEntry::HasFieldPresent);
   converter->RegisterCustomValueField<bool>(
       kRemovedField, &DocumentEntry::removed_, &DocumentEntry::HasFieldPresent);
+  converter->RegisterCustomValueField<int64>(
+      kChangestampField, &DocumentEntry::changestamp_,
+      &DocumentEntry::ParseChangestamp);
 }
 
 std::string DocumentEntry::GetHostedDocumentExtension() const {