Don't use a global share group for the passthrough command buffer contexts.

gpu/ipc/service/gpu_command_buffer_stub.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef GPU_IPC_SERVICE_GPU_COMMAND_BUFFER_STUB_H_
 #define GPU_IPC_SERVICE_GPU_COMMAND_BUFFER_STUB_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 19 matching lines @@
 #include "ipc/ipc_listener.h"
 #include "ipc/ipc_sender.h"
 #include "ui/events/latency_info.h"
 #include "ui/gfx/geometry/size.h"
 #include "ui/gfx/gpu_memory_buffer.h"
 #include "ui/gfx/swap_result.h"
 #include "ui/gl/gl_surface.h"
 #include "ui/gl/gpu_preference.h"
 #include "url/gurl.h"
 
+namespace gl {
+class GLShareGroup;
+}
+
 namespace gpu {
 struct Mailbox;
 struct SyncToken;
 class SyncPointClient;
 }
 
 struct GPUCreateCommandBufferConfig;
 struct GpuCommandBufferMsg_CreateImage_Params;
 
 namespace gpu {
@@ skipping 176 matching lines @@
   const CommandBufferId command_buffer_id_;
   const int32_t stream_id_;
   const int32_t route_id_;
   uint32_t last_flush_count_;
 
   std::unique_ptr<CommandBufferService> command_buffer_;
   std::unique_ptr<gles2::GLES2Decoder> decoder_;
   std::unique_ptr<CommandExecutor> executor_;
   std::unique_ptr<SyncPointClient> sync_point_client_;
   scoped_refptr<gl::GLSurface> surface_;
+  scoped_refptr<gl::GLShareGroup> share_group_;
 
   base::ObserverList<DestructionObserver> destruction_observers_;
 
   bool waiting_for_sync_point_;
 
   base::TimeTicks process_delayed_work_time_;
   uint32_t previous_processed_num_;
   base::TimeTicks last_idle_time_;
 
   LatencyInfoCallback latency_info_callback_;
 
   GURL active_url_;
   size_t active_url_hash_;
 
   std::unique_ptr<WaitForCommandState> wait_for_token_;
   std::unique_ptr<WaitForCommandState> wait_for_get_offset_;
 
   DISALLOW_COPY_AND_ASSIGN(GpuCommandBufferStub);
 };
 
 }  // namespace gpu
 
 #endif  // GPU_IPC_SERVICE_GPU_COMMAND_BUFFER_STUB_H_