Fix crash caused by concurrent access to framebuffer_combo_complete_map_.

gpu/command_buffer/service/context_group_unittest.cc

Index: gpu/command_buffer/service/context_group_unittest.cc
diff --git a/gpu/command_buffer/service/context_group_unittest.cc b/gpu/command_buffer/service/context_group_unittest.cc
index 7c6d5c1c8bd73065051ba8ec1c9ac3f47c58a97d..cbb36f56bf22a0482d9b86bae77d9d7b0a54b5f3 100644
--- a/gpu/command_buffer/service/context_group_unittest.cc
+++ b/gpu/command_buffer/service/context_group_unittest.cc
@@ -41,7 +41,7 @@ class ContextGroupTest : public GpuServiceTest {
     GpuServiceTest::SetUp();
     decoder_.reset(new MockGLES2Decoder());
     group_ = scoped_refptr<ContextGroup>(new ContextGroup(
-        NULL, NULL, NULL, NULL, NULL, NULL, kBindGeneratesResource));
+        NULL, NULL, NULL, NULL, NULL, NULL, NULL, kBindGeneratesResource));
   }
 
   scoped_ptr<MockGLES2Decoder> decoder_;