Pull in various gpu/command_buffer fixes from chromium

gpu/command_buffer/service/context_group.cc

Index: gpu/command_buffer/service/context_group.cc
diff --git a/gpu/command_buffer/service/context_group.cc b/gpu/command_buffer/service/context_group.cc
index d918526ee9043aee8100e5d24e9fab11d982904f..009406631f6134359e424004f2f05856ea7f6fa3 100644
--- a/gpu/command_buffer/service/context_group.cc
+++ b/gpu/command_buffer/service/context_group.cc
@@ -361,10 +361,10 @@ uint32 ContextGroup::GetMemRepresented() const {
   return total;
 }
 
-void ContextGroup::LoseContexts(GLenum reset_status) {
+void ContextGroup::LoseContexts(error::ContextLostReason reason) {
   for (size_t ii = 0; ii < decoders_.size(); ++ii) {
     if (decoders_[ii].get()) {
-      decoders_[ii]->LoseContext(reset_status);
+      decoders_[ii]->MarkContextLost(reason);
     }
   }
 }