gpu: Do not call MakeCurrent in wait sync token callback.

gpu/ipc/service/gpu_command_buffer_stub.cc

Index: gpu/ipc/service/gpu_command_buffer_stub.cc
diff --git a/gpu/ipc/service/gpu_command_buffer_stub.cc b/gpu/ipc/service/gpu_command_buffer_stub.cc
index ffa0a3c23bfcac4e0f8bcc846b14be68e04726b1..bfa53ed81777202dd74f2049e9c8d4876db3e015 100644
--- a/gpu/ipc/service/gpu_command_buffer_stub.cc
+++ b/gpu/ipc/service/gpu_command_buffer_stub.cc
@@ -1093,12 +1093,10 @@ void GpuCommandBufferStub::OnWaitSyncTokenCompleted(
   DCHECK(waiting_for_sync_point_);
   TRACE_EVENT_ASYNC_END1("gpu", "WaitSyncTokenCompleted", this,
                          "GpuCommandBufferStub", this);
+  // Don't call PullTextureUpdates here because we can't MakeCurrent if we're
+  // executing commands on another context. The WaitSyncToken command will run
+  // again and call PullTextureUpdates once this command buffer gets scheduled.
   waiting_for_sync_point_ = false;
-
-  gles2::MailboxManager* mailbox_manager = context_group_->mailbox_manager();
-  if (mailbox_manager->UsesSync() && MakeCurrent())
-    mailbox_manager->PullTextureUpdates(sync_token);
-
   executor_->SetScheduled(true);
   channel_->OnStreamRescheduled(stream_id_, true);
 }