drive: Change DriveServiceInterface::GetChangeList's callback type to ChangeListCallback

Move ConvertChangeListToResourceList() call to the callers' side.
Replace ChangeList::set_items() with mutable_items() to efficiently handle data received from the server.

BUG=231125
TEST=unit_tests

Review URL: https://codereview.chromium.org/309463002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@273626 0039d316-1c4b-4281-b951-d872f2087c98

19 files changed, 201 insertions, 189 deletions

diff --git a/chrome/browser/chromeos/drive/job_scheduler.cc b/chrome/browser/chromeos/drive/job_scheduler.cc
index 615178e..9ad7886 100644
--- a/chrome/browser/chromeos/drive/job_scheduler.cc
+++ b/chrome/browser/chromeos/drive/job_scheduler.cc
@@ -10,6 +10,7 @@
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/stringprintf.h"
 #include "chrome/browser/chromeos/drive/file_system_util.h"
+#include "chrome/browser/drive/drive_api_util.h"
 #include "chrome/browser/drive/event_logger.h"
 #include "chrome/common/pref_names.h"
 #include "content/public/browser/browser_thread.h"
@@ -334,7 +335,7 @@ void JobScheduler::GetChangeList(
       &DriveServiceInterface::GetChangeList,
       base::Unretained(drive_service_),
       start_changestamp,
-      base::Bind(&JobScheduler::OnGetResourceListJobDone,
+      base::Bind(&JobScheduler::OnGetChangeListJobDone,
                  weak_ptr_factory_.GetWeakPtr(),
                  new_job->job_info.job_id,
                  callback));
@@ -353,7 +354,7 @@ void JobScheduler::GetRemainingChangeList(
       &DriveServiceInterface::GetRemainingChangeList,
       base::Unretained(drive_service_),
       next_link,
-      base::Bind(&JobScheduler::OnGetResourceListJobDone,
+      base::Bind(&JobScheduler::OnGetChangeListJobDone,
                  weak_ptr_factory_.GetWeakPtr(),
                  new_job->job_info.job_id,
                  callback));
@@ -898,6 +899,22 @@ bool JobScheduler::OnJobDone(JobID job_id, google_apis::GDataErrorCode error) {
   return !should_retry;
 }
 
+void JobScheduler::OnGetChangeListJobDone(
+    JobID job_id,
+    const google_apis::GetResourceListCallback& callback,
+    google_apis::GDataErrorCode error,
+    scoped_ptr<google_apis::ChangeList> change_list) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(!callback.is_null());
+
+  if (OnJobDone(job_id, error)) {
+    callback.Run(error, change_list ?
+                 util::ConvertChangeListToResourceList(*change_list) :
+                 scoped_ptr<google_apis::ResourceList>());
+
+  }
+}
+
 void JobScheduler::OnGetResourceListJobDone(
     JobID job_id,
     const google_apis::GetResourceListCallback& callback,
diff --git a/chrome/browser/chromeos/drive/job_scheduler.h b/chrome/browser/chromeos/drive/job_scheduler.h
index 1078287..e1d0ff6 100644
--- a/chrome/browser/chromeos/drive/job_scheduler.h
+++ b/chrome/browser/chromeos/drive/job_scheduler.h
@@ -275,6 +275,13 @@ class JobScheduler
   // Retries the job if needed and returns false. Otherwise returns true.
   bool OnJobDone(JobID job_id, google_apis::GDataErrorCode error);
 
+  // Callback for job finishing with a ChangeListCallback.
+  void OnGetChangeListJobDone(
+      JobID job_id,
+      const google_apis::GetResourceListCallback& callback,
+      google_apis::GDataErrorCode error,
+      scoped_ptr<google_apis::ChangeList> change_list);
+
   // Callback for job finishing with a GetResourceListCallback.
   void OnGetResourceListJobDone(
       JobID job_id,
diff --git a/chrome/browser/drive/drive_api_service.cc b/chrome/browser/drive/drive_api_service.cc
index 017dc1a..4df202d 100644
--- a/chrome/browser/drive/drive_api_service.cc
+++ b/chrome/browser/drive/drive_api_service.cc
@@ -31,6 +31,7 @@ using google_apis::AuthStatusCallback;
 using google_apis::AuthorizeAppCallback;
 using google_apis::CancelCallback;
 using google_apis::ChangeList;
+using google_apis::ChangeListCallback;
 using google_apis::DownloadActionCallback;
 using google_apis::EntryActionCallback;
 using google_apis::FileList;
@@ -185,35 +186,6 @@ void ConvertFileListToResourceListOnBlockingPoolAndRun(
       base::Bind(&DidConvertToResourceListOnBlockingPool, callback));
 }
 
-// Thin adapter of ConvertChangeListToResourceList.
-scoped_ptr<ResourceList> ConvertChangeListToResourceList(
-    scoped_ptr<ChangeList> change_list) {
-  return util::ConvertChangeListToResourceList(*change_list);
-}
-
-// Converts the FileList value to ResourceList on blocking pool and runs
-// |callback| on the UI thread.
-void ConvertChangeListToResourceListOnBlockingPoolAndRun(
-    scoped_refptr<base::TaskRunner> blocking_task_runner,
-    const GetResourceListCallback& callback,
-    GDataErrorCode error,
-    scoped_ptr<ChangeList> value) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  DCHECK(!callback.is_null());
-
-  if (!value) {
-    callback.Run(error, scoped_ptr<ResourceList>());
-    return;
-  }
-
-  // Convert the value on blocking pool.
-  base::PostTaskAndReplyWithResult(
-      blocking_task_runner.get(),
-      FROM_HERE,
-      base::Bind(&ConvertChangeListToResourceList, base::Passed(&value)),
-      base::Bind(&DidConvertToResourceListOnBlockingPool, callback));
-}
-
 // Converts the FileResource value to ResourceEntry for upload range request,
 // and runs |callback| on the UI thread.
 void ConvertFileResourceToResourceEntryForUploadRangeAndRun(
@@ -435,14 +407,12 @@ CancelCallback DriveAPIService::SearchByTitle(
 
 CancelCallback DriveAPIService::GetChangeList(
     int64 start_changestamp,
-    const GetResourceListCallback& callback) {
+    const ChangeListCallback& callback) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(!callback.is_null());
 
   ChangesListRequest* request = new ChangesListRequest(
-      sender_.get(), url_generator_,
-      base::Bind(&ConvertChangeListToResourceListOnBlockingPoolAndRun,
-                 blocking_task_runner_, callback));
+      sender_.get(), url_generator_, callback);
   request->set_max_results(kMaxNumFilesResourcePerRequest);
   request->set_start_change_id(start_changestamp);
   request->set_fields(kChangeListFields);
@@ -451,15 +421,13 @@ CancelCallback DriveAPIService::GetChangeList(
 
 CancelCallback DriveAPIService::GetRemainingChangeList(
     const GURL& next_link,
-    const GetResourceListCallback& callback) {
+    const ChangeListCallback& callback) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(!next_link.is_empty());
   DCHECK(!callback.is_null());
 
   ChangesListNextPageRequest* request = new ChangesListNextPageRequest(
-      sender_.get(),
-      base::Bind(&ConvertChangeListToResourceListOnBlockingPoolAndRun,
-                 blocking_task_runner_, callback));
+      sender_.get(), callback);
   request->set_next_link(next_link);
   request->set_fields(kChangeListFields);
   return sender_->StartRequestWithRetry(request);
diff --git a/chrome/browser/drive/drive_api_service.h b/chrome/browser/drive/drive_api_service.h
index a43fe05..cc4c49a 100644
--- a/chrome/browser/drive/drive_api_service.h
+++ b/chrome/browser/drive/drive_api_service.h
@@ -88,10 +88,10 @@ class DriveAPIService : public DriveServiceInterface,
       const google_apis::GetResourceListCallback& callback) OVERRIDE;
   virtual google_apis::CancelCallback GetChangeList(
       int64 start_changestamp,
-      const google_apis::GetResourceListCallback& callback) OVERRIDE;
+      const google_apis::ChangeListCallback& callback) OVERRIDE;
   virtual google_apis::CancelCallback GetRemainingChangeList(
       const GURL& next_link,
-      const google_apis::GetResourceListCallback& callback) OVERRIDE;
+      const google_apis::ChangeListCallback& callback) OVERRIDE;
   virtual google_apis::CancelCallback GetRemainingFileList(
       const GURL& next_link,
       const google_apis::GetResourceListCallback& callback) OVERRIDE;
diff --git a/chrome/browser/drive/drive_service_interface.h b/chrome/browser/drive/drive_service_interface.h
index 1b393d6..ae46e6b 100644
--- a/chrome/browser/drive/drive_service_interface.h
+++ b/chrome/browser/drive/drive_service_interface.h
@@ -198,9 +198,9 @@ class DriveServiceInterface {
   // |callback| must not be null.
   virtual google_apis::CancelCallback GetChangeList(
       int64 start_changestamp,
-      const google_apis::GetResourceListCallback& callback) = 0;
+      const google_apis::ChangeListCallback& callback) = 0;
 
-  // The result of GetChangeList() and GetAllResourceList() may be paged.
+  // The result of GetChangeList() may be paged.
   // In such a case, a next link to fetch remaining result is returned.
   // The page token can be used for this method. |callback| will be called upon
   // completion.
@@ -208,12 +208,12 @@ class DriveServiceInterface {
   // |next_link| must not be empty. |callback| must not be null.
   virtual google_apis::CancelCallback GetRemainingChangeList(
       const GURL& next_link,
-      const google_apis::GetResourceListCallback& callback) = 0;
+      const google_apis::ChangeListCallback& callback) = 0;
 
-  // The result of GetResourceListInDirectory(), Search() and SearchByTitle()
-  // may be paged. In such a case, a next link to fetch remaining result is
-  // returned. The page token can be used for this method. |callback| will be
-  // called upon completion.
+  // The result of GetAllResourceList(), GetResourceListInDirectory(), Search()
+  // and SearchByTitle() may be paged. In such a case, a next link to fetch
+  // remaining result is returned. The page token can be used for this method.
+  // |callback| will be called upon completion.
   //
   // |next_link| must not be empty. |callback| must not be null.
   virtual google_apis::CancelCallback GetRemainingFileList(
diff --git a/chrome/browser/drive/dummy_drive_service.cc b/chrome/browser/drive/dummy_drive_service.cc
index 1528c15..0094ddf 100644
--- a/chrome/browser/drive/dummy_drive_service.cc
+++ b/chrome/browser/drive/dummy_drive_service.cc
@@ -12,6 +12,7 @@ using google_apis::AppListCallback;
 using google_apis::AuthStatusCallback;
 using google_apis::AuthorizeAppCallback;
 using google_apis::CancelCallback;
+using google_apis::ChangeListCallback;
 using google_apis::DownloadActionCallback;
 using google_apis::EntryActionCallback;
 using google_apis::GetContentCallback;
@@ -74,11 +75,11 @@ CancelCallback DummyDriveService::SearchByTitle(
 
 CancelCallback DummyDriveService::GetChangeList(
     int64 start_changestamp,
-    const GetResourceListCallback& callback) { return CancelCallback(); }
+    const ChangeListCallback& callback) { return CancelCallback(); }
 
 CancelCallback DummyDriveService::GetRemainingChangeList(
     const GURL& next_link,
-    const GetResourceListCallback& callback) { return CancelCallback(); }
+    const ChangeListCallback& callback) { return CancelCallback(); }
 
 CancelCallback DummyDriveService::GetRemainingFileList(
     const GURL& next_link,
diff --git a/chrome/browser/drive/dummy_drive_service.h b/chrome/browser/drive/dummy_drive_service.h
index ce6ee94..9882cdda 100644
--- a/chrome/browser/drive/dummy_drive_service.h
+++ b/chrome/browser/drive/dummy_drive_service.h
@@ -44,10 +44,10 @@ class DummyDriveService : public DriveServiceInterface {
       const google_apis::GetResourceListCallback& callback) OVERRIDE;
   virtual google_apis::CancelCallback GetChangeList(
       int64 start_changestamp,
-      const google_apis::GetResourceListCallback& callback) OVERRIDE;
+      const google_apis::ChangeListCallback& callback) OVERRIDE;
   virtual google_apis::CancelCallback GetRemainingChangeList(
       const GURL& next_link,
-      const google_apis::GetResourceListCallback& callback) OVERRIDE;
+      const google_apis::ChangeListCallback& callback) OVERRIDE;
   virtual google_apis::CancelCallback GetRemainingFileList(
       const GURL& next_link,
       const google_apis::GetResourceListCallback& callback) OVERRIDE;
diff --git a/chrome/browser/drive/fake_drive_service.cc b/chrome/browser/drive/fake_drive_service.cc
index 971b7c4..2c87fe6 100644
--- a/chrome/browser/drive/fake_drive_service.cc
+++ b/chrome/browser/drive/fake_drive_service.cc
@@ -33,6 +33,8 @@ using google_apis::AppListCallback;
 using google_apis::AuthStatusCallback;
 using google_apis::AuthorizeAppCallback;
 using google_apis::CancelCallback;
+using google_apis::ChangeList;
+using google_apis::ChangeListCallback;
 using google_apis::ChangeResource;
 using google_apis::DownloadActionCallback;
 using google_apis::EntryActionCallback;
@@ -70,7 +72,7 @@ namespace {
 // - Phrases quoted by double/single quotes
 // - AND search for multiple words/phrases segmented by space
 // - Limited attribute search.  Only "title:" is supported.
-bool EntryMatchWithQuery(const ResourceEntry& entry,
+bool EntryMatchWithQuery(const ChangeResource& entry,
                          const std::string& query) {
   base::StringTokenizer tokenizer(query, " ");
   tokenizer.set_quote_chars("\"'");
@@ -94,7 +96,8 @@ bool EntryMatchWithQuery(const ResourceEntry& entry,
     if (!key.empty() && key != "title")
       return false;
     // Search query in the title.
-    if (entry.title().find(value) == std::string::npos)
+    if (!entry.file() ||
+        entry.file()->title().find(value) == std::string::npos)
       return false;
   }
   return true;
@@ -120,6 +123,14 @@ void EntryActionCallbackAdapter(
   callback.Run(error);
 }
 
+void GetResourceListCallbackAdapter(const GetResourceListCallback& callback,
+                                    GDataErrorCode error,
+                                    scoped_ptr<ChangeList> change_list) {
+  callback.Run(error, change_list ?
+               util::ConvertChangeListToResourceList(*change_list) :
+               scoped_ptr<ResourceList>());
+}
+
 }  // namespace
 
 struct FakeDriveService::EntryInfo {
@@ -275,7 +286,8 @@ CancelCallback FakeDriveService::GetAllResourceList(
                           0,  // start offset
                           default_max_results_,
                           &resource_list_load_count_,
-                          callback);
+                          base::Bind(&GetResourceListCallbackAdapter,
+                                     callback));
   return CancelCallback();
 }
 
@@ -292,7 +304,8 @@ CancelCallback FakeDriveService::GetResourceListInDirectory(
                           0,  // start offset
                           default_max_results_,
                           &directory_load_count_,
-                          callback);
+                          base::Bind(&GetResourceListCallbackAdapter,
+                                     callback));
   return CancelCallback();
 }
 
@@ -309,7 +322,8 @@ CancelCallback FakeDriveService::Search(
                           0,  // start offset
                           default_max_results_,
                           NULL,
-                          callback);
+                          base::Bind(&GetResourceListCallbackAdapter,
+                                     callback));
   return CancelCallback();
 }
 
@@ -329,13 +343,14 @@ CancelCallback FakeDriveService::SearchByTitle(
                           0,  // start offset
                           default_max_results_,
                           NULL,
-                          callback);
+                          base::Bind(&GetResourceListCallbackAdapter,
+                                     callback));
   return CancelCallback();
 }
 
 CancelCallback FakeDriveService::GetChangeList(
     int64 start_changestamp,
-    const GetResourceListCallback& callback) {
+    const ChangeListCallback& callback) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(!callback.is_null());
 
@@ -351,7 +366,7 @@ CancelCallback FakeDriveService::GetChangeList(
 
 CancelCallback FakeDriveService::GetRemainingChangeList(
     const GURL& next_link,
-    const GetResourceListCallback& callback) {
+    const ChangeListCallback& callback) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(!next_link.is_empty());
   DCHECK(!callback.is_null());
@@ -404,7 +419,8 @@ CancelCallback FakeDriveService::GetRemainingFileList(
   DCHECK(!next_link.is_empty());
   DCHECK(!callback.is_null());
 
-  return GetRemainingChangeList(next_link, callback);
+  return GetRemainingChangeList(
+      next_link, base::Bind(&GetResourceListCallbackAdapter, callback));
 }
 
 CancelCallback FakeDriveService::GetResourceEntry(
@@ -1376,24 +1392,23 @@ void FakeDriveService::GetResourceListInternal(
     int start_offset,
     int max_results,
     int* load_counter,
-    const GetResourceListCallback& callback) {
+    const ChangeListCallback& callback) {
   if (offline_) {
     base::MessageLoop::current()->PostTask(
         FROM_HERE,
         base::Bind(callback,
                    GDATA_NO_CONNECTION,
-                   base::Passed(scoped_ptr<ResourceList>())));
+                   base::Passed(scoped_ptr<ChangeList>())));
     return;
   }
 
   // Filter out entries per parameters like |directory_resource_id| and
   // |search_query|.
-  ScopedVector<ResourceEntry> entries;
+  ScopedVector<ChangeResource> entries;
   int num_entries_matched = 0;
   for (EntryInfoMap::iterator it = entries_.begin(); it != entries_.end();
        ++it) {
-    scoped_ptr<ResourceEntry> entry =
-        util::ConvertChangeResourceToResourceEntry(it->second->change_resource);
+    const ChangeResource& entry = it->second->change_resource;
     bool should_exclude = false;
 
     // If |directory_resource_id| is set, exclude the entry if it's not in
@@ -1401,13 +1416,9 @@ void FakeDriveService::GetResourceListInternal(
     if (!directory_resource_id.empty()) {
       // Get the parent resource ID of the entry.
       std::string parent_resource_id;
-      const google_apis::Link* parent_link =
-          entry->GetLinkByType(Link::LINK_PARENT);
-      if (parent_link) {
-        parent_resource_id =
-            net::UnescapeURLComponent(parent_link->href().ExtractFileName(),
-                                      net::UnescapeRule::URL_SPECIAL_CHARS);
-      }
+      if (entry.file() && !entry.file()->parents().empty())
+        parent_resource_id = entry.file()->parents()[0].file_id();
+
       if (directory_resource_id != parent_resource_id)
         should_exclude = true;
     }
@@ -1415,7 +1426,7 @@ void FakeDriveService::GetResourceListInternal(
     // If |search_query| is set, exclude the entry if it does not contain the
     // search query in the title.
     if (!should_exclude && !search_query.empty() &&
-        !EntryMatchWithQuery(*entry, search_query)) {
+        !EntryMatchWithQuery(entry, search_query)) {
       should_exclude = true;
     }
 
@@ -1423,12 +1434,14 @@ void FakeDriveService::GetResourceListInternal(
     // changestamp is older than |largest_changestamp|.
     // See https://developers.google.com/google-apps/documents-list/
     // #retrieving_all_changes_since_a_given_changestamp
-    if (start_changestamp > 0 && entry->changestamp() < start_changestamp)
+    if (start_changestamp > 0 && entry.change_id() < start_changestamp)
       should_exclude = true;
 
     // If the caller requests other list than change list by specifying
     // zero-|start_changestamp|, exclude deleted entry from the result.
-    if (!start_changestamp && entry->deleted())
+    const bool deleted = entry.is_deleted() ||
+        (entry.file() && entry.file()->labels().is_trashed());
+    if (!start_changestamp && deleted)
       should_exclude = true;
 
     // The entry matched the criteria for inclusion.
@@ -1441,14 +1454,23 @@ void FakeDriveService::GetResourceListInternal(
     if (start_offset > 0 && num_entries_matched <= start_offset)
       should_exclude = true;
 
-    if (!should_exclude)
-      entries.push_back(entry.release());
+    if (!should_exclude) {
+      scoped_ptr<ChangeResource> entry_copied(new ChangeResource);
+      entry_copied->set_change_id(entry.change_id());
+      entry_copied->set_file_id(entry.file_id());
+      entry_copied->set_deleted(entry.is_deleted());
+      if (entry.file()) {
+        entry_copied->set_file(
+            make_scoped_ptr(new FileResource(*entry.file())));
+      }
+      entry_copied->set_modification_date(entry.modification_date());
+      entries.push_back(entry_copied.release());
+    }
   }
 
-  scoped_ptr<ResourceList> resource_list(new ResourceList);
+  scoped_ptr<ChangeList> change_list(new ChangeList);
   if (start_changestamp > 0 && start_offset == 0) {
-    resource_list->set_largest_changestamp(
-        about_resource_->largest_change_id());
+    change_list->set_largest_change_id(about_resource_->largest_change_id());
   }
 
   // If |max_results| is set, trim the entries if the number exceeded the max
@@ -1477,18 +1499,15 @@ void FakeDriveService::GetResourceListInternal(
           next_url, "parent", directory_resource_id);
     }
 
-    Link* link = new Link;
-    link->set_type(Link::LINK_NEXT);
-    link->set_href(next_url);
-    resource_list->mutable_links()->push_back(link);
+    change_list->set_next_link(next_url);
   }
-  resource_list->set_entries(entries.Pass());
+  *change_list->mutable_items() = entries.Pass();
 
   if (load_counter)
     *load_counter += 1;
   base::MessageLoop::current()->PostTask(
       FROM_HERE,
-      base::Bind(callback, HTTP_SUCCESS, base::Passed(&resource_list)));
+      base::Bind(callback, HTTP_SUCCESS, base::Passed(&change_list)));
 }
 
 GURL FakeDriveService::GetNewUploadSessionUrl() {
diff --git a/chrome/browser/drive/fake_drive_service.h b/chrome/browser/drive/fake_drive_service.h
index 738c621..eb0d8ec 100644
--- a/chrome/browser/drive/fake_drive_service.h
+++ b/chrome/browser/drive/fake_drive_service.h
@@ -130,10 +130,10 @@ class FakeDriveService : public DriveServiceInterface {
       const google_apis::GetResourceListCallback& callback) OVERRIDE;
   virtual google_apis::CancelCallback GetChangeList(
       int64 start_changestamp,
-      const google_apis::GetResourceListCallback& callback) OVERRIDE;
+      const google_apis::ChangeListCallback& callback) OVERRIDE;
   virtual google_apis::CancelCallback GetRemainingChangeList(
       const GURL& next_link,
-      const google_apis::GetResourceListCallback& callback) OVERRIDE;
+      const google_apis::ChangeListCallback& callback) OVERRIDE;
   virtual google_apis::CancelCallback GetRemainingFileList(
       const GURL& next_link,
       const google_apis::GetResourceListCallback& callback) OVERRIDE;
@@ -311,7 +311,7 @@ class FakeDriveService : public DriveServiceInterface {
       int start_offset,
       int max_results,
       int* load_counter,
-      const google_apis::GetResourceListCallback& callback);
+      const google_apis::ChangeListCallback& callback);
 
   // Returns new upload session URL.
   GURL GetNewUploadSessionUrl();
diff --git a/chrome/browser/drive/fake_drive_service_unittest.cc b/chrome/browser/drive/fake_drive_service_unittest.cc
index e592323..9e050c7 100644
--- a/chrome/browser/drive/fake_drive_service_unittest.cc
+++ b/chrome/browser/drive/fake_drive_service_unittest.cc
@@ -24,6 +24,8 @@
 
 using google_apis::AboutResource;
 using google_apis::AppList;
+using google_apis::ChangeList;
+using google_apis::ChangeResource;
 using google_apis::GDATA_NO_CONNECTION;
 using google_apis::GDATA_OTHER_ERROR;
 using google_apis::GDataErrorCode;
@@ -374,19 +376,19 @@ TEST_F(FakeDriveServiceTest, GetChangeList_NoNewEntries) {
   ASSERT_TRUE(test_util::SetUpTestEntries(&fake_service_));
 
   GDataErrorCode error = GDATA_OTHER_ERROR;
-  scoped_ptr<ResourceList> resource_list;
+  scoped_ptr<ChangeList> change_list;
   fake_service_.GetChangeList(
       fake_service_.about_resource().largest_change_id() + 1,
-      test_util::CreateCopyResultCallback(&error, &resource_list));
+      test_util::CreateCopyResultCallback(&error, &change_list));
   base::RunLoop().RunUntilIdle();
 
   EXPECT_EQ(HTTP_SUCCESS, error);
-  ASSERT_TRUE(resource_list);
+  ASSERT_TRUE(change_list);
   EXPECT_EQ(fake_service_.about_resource().largest_change_id(),
-            resource_list->largest_changestamp());
+            change_list->largest_change_id());
   // This should be empty as the latest changestamp was passed to
   // GetResourceList(), hence there should be no new entries.
-  EXPECT_EQ(0U, resource_list->entries().size());
+  EXPECT_EQ(0U, change_list->items().size());
   // It's considered loaded even if the result is empty.
   EXPECT_EQ(1, fake_service_.change_list_load_count());
 }
@@ -402,19 +404,20 @@ TEST_F(FakeDriveServiceTest, GetChangeList_WithNewEntry) {
 
   // Get the resource list newer than old_largest_change_id.
   GDataErrorCode error = GDATA_OTHER_ERROR;
-  scoped_ptr<ResourceList> resource_list;
+  scoped_ptr<ChangeList> change_list;
   fake_service_.GetChangeList(
       old_largest_change_id + 1,
-      test_util::CreateCopyResultCallback(&error, &resource_list));
+      test_util::CreateCopyResultCallback(&error, &change_list));
   base::RunLoop().RunUntilIdle();
 
   EXPECT_EQ(HTTP_SUCCESS, error);
-  ASSERT_TRUE(resource_list);
+  ASSERT_TRUE(change_list);
   EXPECT_EQ(fake_service_.about_resource().largest_change_id(),
-            resource_list->largest_changestamp());
+            change_list->largest_change_id());
   // The result should only contain the newly created directory.
-  ASSERT_EQ(1U, resource_list->entries().size());
-  EXPECT_EQ("new directory", resource_list->entries()[0]->title());
+  ASSERT_EQ(1U, change_list->items().size());
+  ASSERT_TRUE(change_list->items()[0]->file());
+  EXPECT_EQ("new directory", change_list->items()[0]->file()->title());
   EXPECT_EQ(1, fake_service_.change_list_load_count());
 }
 
@@ -423,14 +426,14 @@ TEST_F(FakeDriveServiceTest, GetChangeList_Offline) {
   fake_service_.set_offline(true);
 
   GDataErrorCode error = GDATA_OTHER_ERROR;
-  scoped_ptr<ResourceList> resource_list;
+  scoped_ptr<ChangeList> change_list;
   fake_service_.GetChangeList(
       654321,  // start_changestamp
-      test_util::CreateCopyResultCallback(&error, &resource_list));
+      test_util::CreateCopyResultCallback(&error, &change_list));
   base::RunLoop().RunUntilIdle();
 
   EXPECT_EQ(GDATA_NO_CONNECTION, error);
-  EXPECT_FALSE(resource_list);
+  EXPECT_FALSE(change_list);
 }
 
 TEST_F(FakeDriveServiceTest, GetChangeList_DeletedEntry) {
@@ -449,22 +452,22 @@ TEST_F(FakeDriveServiceTest, GetChangeList_DeletedEntry) {
 
   // Get the resource list newer than old_largest_change_id.
   error = GDATA_OTHER_ERROR;
-  scoped_ptr<ResourceList> resource_list;
+  scoped_ptr<ChangeList> change_list;
   fake_service_.GetChangeList(
       old_largest_change_id + 1,
-      test_util::CreateCopyResultCallback(&error, &resource_list));
+      test_util::CreateCopyResultCallback(&error, &change_list));
   base::RunLoop().RunUntilIdle();
 
   EXPECT_EQ(HTTP_SUCCESS, error);
-  ASSERT_TRUE(resource_list);
+  ASSERT_TRUE(change_list);
   EXPECT_EQ(fake_service_.about_resource().largest_change_id(),
-            resource_list->largest_changestamp());
+            change_list->largest_change_id());
   // The result should only contain the deleted file.
-  ASSERT_EQ(1U, resource_list->entries().size());
-  const ResourceEntry& entry = *resource_list->entries()[0];
-  EXPECT_EQ("file:2_file_resource_id", entry.resource_id());
-  EXPECT_TRUE(entry.title().empty());
-  EXPECT_TRUE(entry.deleted());
+  ASSERT_EQ(1U, change_list->items().size());
+  const ChangeResource& item = *change_list->items()[0];
+  EXPECT_EQ("file:2_file_resource_id", item.file_id());
+  EXPECT_FALSE(item.file());
+  EXPECT_TRUE(item.is_deleted());
   EXPECT_EQ(1, fake_service_.change_list_load_count());
 }
 
@@ -483,25 +486,26 @@ TEST_F(FakeDriveServiceTest, GetChangeList_TrashedEntry) {
 
   // Get the resource list newer than old_largest_change_id.
   error = GDATA_OTHER_ERROR;
-  scoped_ptr<ResourceList> resource_list;
+  scoped_ptr<ChangeList> change_list;
   fake_service_.GetChangeList(
       old_largest_change_id + 1,
-      test_util::CreateCopyResultCallback(&error, &resource_list));
+      test_util::CreateCopyResultCallback(&error, &change_list));
   base::RunLoop().RunUntilIdle();
 
   EXPECT_EQ(HTTP_SUCCESS, error);
-  ASSERT_TRUE(resource_list);
+  ASSERT_TRUE(change_list);
   EXPECT_EQ(fake_service_.about_resource().largest_change_id(),
-            resource_list->largest_changestamp());
+            change_list->largest_change_id());
   // The result should only contain the trashed file.
-  ASSERT_EQ(1U, resource_list->entries().size());
-  const ResourceEntry& entry = *resource_list->entries()[0];
-  EXPECT_EQ("file:2_file_resource_id", entry.resource_id());
-  EXPECT_TRUE(entry.deleted());
+  ASSERT_EQ(1U, change_list->items().size());
+  const ChangeResource& item = *change_list->items()[0];
+  EXPECT_EQ("file:2_file_resource_id", item.file_id());
+  ASSERT_TRUE(item.file());
+  EXPECT_TRUE(item.file()->labels().is_trashed());
   EXPECT_EQ(1, fake_service_.change_list_load_count());
 }
 
-TEST_F(FakeDriveServiceTest, GetRemainingChangeList_GetAllResourceList) {
+TEST_F(FakeDriveServiceTest, GetRemainingFileList_GetAllResourceList) {
   ASSERT_TRUE(test_util::SetUpTestEntries(&fake_service_));
   fake_service_.set_default_max_results(6);
 
@@ -528,7 +532,7 @@ TEST_F(FakeDriveServiceTest, GetRemainingChangeList_GetAllResourceList) {
 
   error = GDATA_OTHER_ERROR;
   resource_list.reset();
-  fake_service_.GetRemainingChangeList(
+  fake_service_.GetRemainingFileList(
       next_url,
       test_util::CreateCopyResultCallback(&error, &resource_list));
   base::RunLoop().RunUntilIdle();
@@ -546,7 +550,7 @@ TEST_F(FakeDriveServiceTest, GetRemainingChangeList_GetAllResourceList) {
 
   error = GDATA_OTHER_ERROR;
   resource_list.reset();
-  fake_service_.GetRemainingChangeList(
+  fake_service_.GetRemainingFileList(
       next_url,
       test_util::CreateCopyResultCallback(&error, &resource_list));
   base::RunLoop().RunUntilIdle();
@@ -669,56 +673,51 @@ TEST_F(FakeDriveServiceTest, GetRemainingChangeList_GetChangeList) {
   }
 
   GDataErrorCode error = GDATA_OTHER_ERROR;
-  scoped_ptr<ResourceList> resource_list;
+  scoped_ptr<ChangeList> change_list;
   fake_service_.GetChangeList(
       old_largest_change_id + 1,  // start_changestamp
-      test_util::CreateCopyResultCallback(&error, &resource_list));
+      test_util::CreateCopyResultCallback(&error, &change_list));
   base::RunLoop().RunUntilIdle();
   EXPECT_EQ(HTTP_SUCCESS, error);
-  ASSERT_TRUE(resource_list);
+  ASSERT_TRUE(change_list);
 
   // Do some sanity check.
   // The number of results is 5 entries. Thus, it should split into three
   // chunks: 2, 2 and then 1.
-  EXPECT_EQ(2U, resource_list->entries().size());
+  EXPECT_EQ(2U, change_list->items().size());
   EXPECT_EQ(1, fake_service_.change_list_load_count());
 
   // Second page loading.
-  const google_apis::Link* next_link =
-      resource_list->GetLinkByType(Link::LINK_NEXT);
-  ASSERT_TRUE(next_link);
-  // Keep the next url before releasing the |resource_list|.
-  GURL next_url(next_link->href());
+  // Keep the next url before releasing the |change_list|.
+  GURL next_url = change_list->next_link();
 
   error = GDATA_OTHER_ERROR;
-  resource_list.reset();
+  change_list.reset();
   fake_service_.GetRemainingChangeList(
       next_url,
-      test_util::CreateCopyResultCallback(&error, &resource_list));
+      test_util::CreateCopyResultCallback(&error, &change_list));
   base::RunLoop().RunUntilIdle();
 
   EXPECT_EQ(HTTP_SUCCESS, error);
-  ASSERT_TRUE(resource_list);
+  ASSERT_TRUE(change_list);
 
-  EXPECT_EQ(2U, resource_list->entries().size());
+  EXPECT_EQ(2U, change_list->items().size());
   EXPECT_EQ(1, fake_service_.change_list_load_count());
 
   // Third page loading.
-  next_link = resource_list->GetLinkByType(Link::LINK_NEXT);
-  ASSERT_TRUE(next_link);
-  next_url = GURL(next_link->href());
+  next_url = change_list->next_link();
 
   error = GDATA_OTHER_ERROR;
-  resource_list.reset();
+  change_list.reset();
   fake_service_.GetRemainingChangeList(
       next_url,
-      test_util::CreateCopyResultCallback(&error, &resource_list));
+      test_util::CreateCopyResultCallback(&error, &change_list));
   base::RunLoop().RunUntilIdle();
 
   EXPECT_EQ(HTTP_SUCCESS, error);
-  ASSERT_TRUE(resource_list);
+  ASSERT_TRUE(change_list);
 
-  EXPECT_EQ(1U, resource_list->entries().size());
+  EXPECT_EQ(1U, change_list->items().size());
   EXPECT_EQ(1, fake_service_.change_list_load_count());
 }
 
diff --git a/chrome/browser/sync_file_system/drive_backend/drive_service_on_worker.cc b/chrome/browser/sync_file_system/drive_backend/drive_service_on_worker.cc
index 0afa45c..39ce2d4 100644
--- a/chrome/browser/sync_file_system/drive_backend/drive_service_on_worker.cc
+++ b/chrome/browser/sync_file_system/drive_backend/drive_service_on_worker.cc
@@ -111,7 +111,7 @@ google_apis::CancelCallback DriveServiceOnWorker::GetAboutResource(
 
 google_apis::CancelCallback DriveServiceOnWorker::GetChangeList(
     int64 start_changestamp,
-    const google_apis::GetResourceListCallback& callback) {
+    const google_apis::ChangeListCallback& callback) {
   ui_task_runner_->PostTask(
       FROM_HERE,
       base::Bind(&DriveServiceWrapper::GetChangeList,
@@ -127,7 +127,7 @@ google_apis::CancelCallback DriveServiceOnWorker::GetChangeList(
 
 google_apis::CancelCallback DriveServiceOnWorker::GetRemainingChangeList(
     const GURL& next_link,
-    const google_apis::GetResourceListCallback& callback) {
+    const google_apis::ChangeListCallback& callback) {
   ui_task_runner_->PostTask(
       FROM_HERE,
       base::Bind(&DriveServiceWrapper::GetRemainingChangeList,
diff --git a/chrome/browser/sync_file_system/drive_backend/drive_service_on_worker.h b/chrome/browser/sync_file_system/drive_backend/drive_service_on_worker.h
index 82f988a..66b8a9e 100644
--- a/chrome/browser/sync_file_system/drive_backend/drive_service_on_worker.h
+++ b/chrome/browser/sync_file_system/drive_backend/drive_service_on_worker.h
@@ -54,11 +54,11 @@ class DriveServiceOnWorker : public drive::DriveServiceInterface {
 
   virtual google_apis::CancelCallback GetChangeList(
       int64 start_changestamp,
-      const google_apis::GetResourceListCallback& callback) OVERRIDE;
+      const google_apis::ChangeListCallback& callback) OVERRIDE;
 
   virtual google_apis::CancelCallback GetRemainingChangeList(
       const GURL& next_link,
-      const google_apis::GetResourceListCallback& callback) OVERRIDE;
+      const google_apis::ChangeListCallback& callback) OVERRIDE;
 
   virtual std::string GetRootResourceId() const OVERRIDE;
 
diff --git a/chrome/browser/sync_file_system/drive_backend/drive_service_wrapper.cc b/chrome/browser/sync_file_system/drive_backend/drive_service_wrapper.cc
index d0facd0..24f4476 100644
--- a/chrome/browser/sync_file_system/drive_backend/drive_service_wrapper.cc
+++ b/chrome/browser/sync_file_system/drive_backend/drive_service_wrapper.cc
@@ -58,13 +58,13 @@ void DriveServiceWrapper::GetAboutResource(
 
 void DriveServiceWrapper::GetChangeList(
     int64 start_changestamp,
-    const google_apis::GetResourceListCallback& callback) {
+    const google_apis::ChangeListCallback& callback) {
   drive_service_->GetChangeList(start_changestamp, callback);
 }
 
 void DriveServiceWrapper::GetRemainingChangeList(
     const GURL& next_link,
-    const google_apis::GetResourceListCallback& callback) {
+    const google_apis::ChangeListCallback& callback) {
   drive_service_->GetRemainingChangeList(next_link, callback);
 }
 
diff --git a/chrome/browser/sync_file_system/drive_backend/drive_service_wrapper.h b/chrome/browser/sync_file_system/drive_backend/drive_service_wrapper.h
index 75b27cb..1c2efde 100644
--- a/chrome/browser/sync_file_system/drive_backend/drive_service_wrapper.h
+++ b/chrome/browser/sync_file_system/drive_backend/drive_service_wrapper.h
@@ -42,11 +42,11 @@ class DriveServiceWrapper : public base::SupportsWeakPtr<DriveServiceWrapper> {
 
   void GetChangeList(
       int64 start_changestamp,
-      const google_apis::GetResourceListCallback& callback);
+      const google_apis::ChangeListCallback& callback);
 
   void GetRemainingChangeList(
       const GURL& next_link,
-      const google_apis::GetResourceListCallback& callback);
+      const google_apis::ChangeListCallback& callback);
 
   void GetRemainingFileList(
       const GURL& next_link,
diff --git a/chrome/browser/sync_file_system/drive_backend/list_changes_task.cc b/chrome/browser/sync_file_system/drive_backend/list_changes_task.cc
index 0b97960..3197a1c 100644
--- a/chrome/browser/sync_file_system/drive_backend/list_changes_task.cc
+++ b/chrome/browser/sync_file_system/drive_backend/list_changes_task.cc
@@ -7,7 +7,6 @@
 #include "base/bind.h"
 #include "base/format_macros.h"
 #include "base/location.h"
-#include "chrome/browser/drive/drive_api_util.h"
 #include "chrome/browser/drive/drive_service_interface.h"
 #include "chrome/browser/sync_file_system/drive_backend/drive_backend_util.h"
 #include "chrome/browser/sync_file_system/drive_backend/metadata_database.h"
@@ -23,22 +22,6 @@
 namespace sync_file_system {
 namespace drive_backend {
 
-namespace {
-
-scoped_ptr<google_apis::ChangeResource> ConvertResourceEntryToChangeResource(
-    const google_apis::ResourceEntry& entry) {
-  scoped_ptr<google_apis::ChangeResource> out(new google_apis::ChangeResource);
-  out->set_file_id(entry.resource_id());
-  if (!entry.deleted())
-    out->set_file(drive::util::ConvertResourceEntryToFileResource(entry));
-  out->set_change_id(entry.changestamp());
-  out->set_deleted(entry.deleted());
-
-  return out.Pass();
-}
-
-}  // namespace
-
 ListChangesTask::ListChangesTask(SyncEngineContext* sync_context)
     : sync_context_(sync_context),
       weak_ptr_factory_(this) {
@@ -76,7 +59,7 @@ void ListChangesTask::StartListing(scoped_ptr<SyncTaskToken> token) {
 void ListChangesTask::DidListChanges(
     scoped_ptr<SyncTaskToken> token,
     google_apis::GDataErrorCode error,
-    scoped_ptr<google_apis::ResourceList> resource_list) {
+    scoped_ptr<google_apis::ChangeList> change_list) {
   SyncStatusCode status = GDataErrorCodeToSyncStatusCode(error);
   if (status != SYNC_STATUS_OK) {
     util::Log(logging::LOG_VERBOSE, FROM_HERE,
@@ -86,7 +69,7 @@ void ListChangesTask::DidListChanges(
     return;
   }
 
-  if (!resource_list) {
+  if (!change_list) {
     NOTREACHED();
     util::Log(logging::LOG_VERBOSE, FROM_HERE,
               "[Changes] Got invalid change list.");
@@ -95,16 +78,16 @@ void ListChangesTask::DidListChanges(
     return;
   }
 
-  change_list_.reserve(change_list_.size() + resource_list->entries().size());
-  for (size_t i = 0; i < resource_list->entries().size(); ++i) {
-    change_list_.push_back(ConvertResourceEntryToChangeResource(
-        *resource_list->entries()[i]).release());
-  }
+  std::vector<google_apis::ChangeResource*> changes;
+  change_list->mutable_items()->release(&changes);
+
+  change_list_.reserve(change_list_.size() + changes.size());
+  for (size_t i = 0; i < changes.size(); ++i)
+    change_list_.push_back(changes[i]);
 
-  GURL next_feed;
-  if (resource_list->GetNextFeedURL(&next_feed)) {
+  if (!change_list->next_link().is_empty()) {
     drive_service()->GetRemainingChangeList(
-        next_feed,
+        change_list->next_link(),
         base::Bind(
             &ListChangesTask::DidListChanges,
             weak_ptr_factory_.GetWeakPtr(),
@@ -126,7 +109,7 @@ void ListChangesTask::DidListChanges(
       blocking_factor.Pass(),
       base::Bind(&ListChangesTask::CheckInChangeList,
                  weak_ptr_factory_.GetWeakPtr(),
-                 resource_list->largest_changestamp()));
+                 change_list->largest_change_id()));
 }
 
 void ListChangesTask::CheckInChangeList(int64 largest_change_id,
diff --git a/chrome/browser/sync_file_system/drive_backend/list_changes_task.h b/chrome/browser/sync_file_system/drive_backend/list_changes_task.h
index 272e788..c594ba3 100644
--- a/chrome/browser/sync_file_system/drive_backend/list_changes_task.h
+++ b/chrome/browser/sync_file_system/drive_backend/list_changes_task.h
@@ -16,8 +16,8 @@ class DriveServiceInterface;
 }
 
 namespace google_apis {
+class ChangeList;
 class ChangeResource;
-class ResourceList;
 }
 
 namespace sync_file_system {
@@ -37,7 +37,7 @@ class ListChangesTask : public SyncTask {
   void StartListing(scoped_ptr<SyncTaskToken> token);
   void DidListChanges(scoped_ptr<SyncTaskToken> token,
                       google_apis::GDataErrorCode error,
-                      scoped_ptr<google_apis::ResourceList> resource_list);
+                      scoped_ptr<google_apis::ChangeList> change_list);
   void CheckInChangeList(int64 largest_change_id,
                          scoped_ptr<SyncTaskToken> token);
 
diff --git a/chrome/browser/sync_file_system/drive_backend_v1/api_util.cc b/chrome/browser/sync_file_system/drive_backend_v1/api_util.cc
index 2ec9791..62c579f 100644
--- a/chrome/browser/sync_file_system/drive_backend_v1/api_util.cc
+++ b/chrome/browser/sync_file_system/drive_backend_v1/api_util.cc
@@ -480,7 +480,7 @@ void APIUtil::ListChanges(int64 start_changestamp,
 
   drive_service_->GetChangeList(
       start_changestamp,
-      base::Bind(&APIUtil::DidGetResourceList, AsWeakPtr(), callback));
+      base::Bind(&APIUtil::DidGetChangeList, AsWeakPtr(), callback));
 }
 
 void APIUtil::ContinueListing(const GURL& next_link,
@@ -675,6 +675,24 @@ void APIUtil::OnConnectionTypeChanged(
   CancelAllUploads(google_apis::GDATA_NO_CONNECTION);
 }
 
+void APIUtil::DidGetChangeList(
+    const ResourceListCallback& callback,
+    google_apis::GDataErrorCode error,
+    scoped_ptr<google_apis::ChangeList> change_list) {
+  DCHECK(CalledOnValidThread());
+
+  if (error != google_apis::HTTP_SUCCESS) {
+    DVLOG(2) << "Error on listing changes: " << error;
+    callback.Run(error, scoped_ptr<google_apis::ResourceList>());
+    return;
+  }
+
+  DVLOG(2) << "Got change list";
+  DCHECK(change_list);
+  callback.Run(error,
+               drive::util::ConvertChangeListToResourceList(*change_list));
+}
+
 void APIUtil::DidGetResourceList(
     const ResourceListCallback& callback,
     google_apis::GDataErrorCode error,
diff --git a/chrome/browser/sync_file_system/drive_backend_v1/api_util.h b/chrome/browser/sync_file_system/drive_backend_v1/api_util.h
index 42180ed..200d852 100644
--- a/chrome/browser/sync_file_system/drive_backend_v1/api_util.h
+++ b/chrome/browser/sync_file_system/drive_backend_v1/api_util.h
@@ -158,6 +158,10 @@ class APIUtil : public APIUtilInterface,
       const std::string& sync_root_resource_id,
       google_apis::GDataErrorCode error);
 
+  void DidGetChangeList(const ResourceListCallback& callback,
+                        google_apis::GDataErrorCode error,
+                        scoped_ptr<google_apis::ChangeList> change_list);
+
   void DidGetResourceList(const ResourceListCallback& callback,
                           google_apis::GDataErrorCode error,
                           scoped_ptr<google_apis::ResourceList> resource_list);
diff --git a/google_apis/drive/drive_api_parser.h b/google_apis/drive/drive_api_parser.h
index 2700dbc..babb4cd 100644
--- a/google_apis/drive/drive_api_parser.h
+++ b/google_apis/drive/drive_api_parser.h
@@ -601,13 +601,11 @@ class FileList {
 
   // Returns a set of files in this list.
   const ScopedVector<FileResource>& items() const { return items_; }
+  ScopedVector<FileResource>* mutable_items() { return &items_; }
 
   void set_next_link(const GURL& next_link) {
     next_link_ = next_link;
   }
-  void set_items(ScopedVector<FileResource> items) {
-    items_ = items.Pass();
-  }
 
  private:
   friend class DriveAPIParserTest;
@@ -715,6 +713,7 @@ class ChangeList {
 
   // Returns a set of changes in this list.
   const ScopedVector<ChangeResource>& items() const { return items_; }
+  ScopedVector<ChangeResource>* mutable_items() { return &items_; }
 
   void set_next_link(const GURL& next_link) {
     next_link_ = next_link;
@@ -722,9 +721,6 @@ class ChangeList {
   void set_largest_change_id(int64 largest_change_id) {
     largest_change_id_ = largest_change_id;
   }
-  void set_items(ScopedVector<ChangeResource> items) {
-    items_ = items.Pass();
-  }
 
  private:
   friend class DriveAPIParserTest;