Handle UNPACK_SKIP_* and PACK_SKIP_* parameters on the client side.

gpu/command_buffer/service/feature_info.cc

Index: gpu/command_buffer/service/feature_info.cc
diff --git a/gpu/command_buffer/service/feature_info.cc b/gpu/command_buffer/service/feature_info.cc
index a0ebe050a743ddc440dd5054683cbb36a29ec389..dcb00461b719718d2da2c7c9ed112ec0759bfc26 100644
--- a/gpu/command_buffer/service/feature_info.cc
+++ b/gpu/command_buffer/service/feature_info.cc
@@ -389,10 +389,9 @@ void FeatureInfo::InitializeFeatures() {
   // Pre es3, there are no PBOS and all unpack state is handled in client side.
   // With es3, unpack state is needed in server side. We always mark these
   // enums as valid and pass them to drivers only when a valid PBO is bound.
+  // UNPACK_ROW_LENGTH, UNPACK_SKIP_ROWS, and UNPACK_SKIP_PIXELS are enabled,
+  // but there is no need to add them to pixel_store validtor.
   AddExtensionString("GL_EXT_unpack_subimage");
-  validators_.pixel_store.AddValue(GL_UNPACK_ROW_LENGTH);
-  validators_.pixel_store.AddValue(GL_UNPACK_SKIP_ROWS);
-  validators_.pixel_store.AddValue(GL_UNPACK_SKIP_PIXELS);
 
   if (feature_flags_.enable_subscribe_uniform) {
     AddExtensionString("GL_CHROMIUM_subscribe_uniform");