Add UninstallApp() method to DriveAPIService interface.

chrome/browser/drive/gdata_wapi_service.cc

Index: chrome/browser/drive/gdata_wapi_service.cc
diff --git a/chrome/browser/drive/gdata_wapi_service.cc b/chrome/browser/drive/gdata_wapi_service.cc
index 18fa50cfae70e22ea03abb50c799af90cbbacf10..e9d9a45456d32335ea25c4528a05ed8665f723c8 100644
--- a/chrome/browser/drive/gdata_wapi_service.cc
+++ b/chrome/browser/drive/gdata_wapi_service.cc
@@ -584,6 +584,18 @@ CancelCallback GDataWapiService::AuthorizeApp(
                               app_id));
 }
 
+CancelCallback GDataWapiService::UninstallApp(
+    const std::string& app_id,
+    const EntryActionCallback& callback) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(!callback.is_null());
+
+  // GData WAPI doesn't support app uninstallation.
+  // This method should never be called if GData WAPI is enabled.
+  NOTREACHED();
+  return CancelCallback();
+}
+
 CancelCallback GDataWapiService::GetResourceListInDirectoryByWapi(
     const std::string& directory_resource_id,
     const google_apis::GetResourceListCallback& callback) {