Compute GpuDriverBugWorkarounds only one time in the GPU process

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 f343e5e2e5853464ae9fc7d3cd3d6e3fb6e0a33b..57fb7ec6dd51eec72d8ed272491a34b89b286660 100644
--- a/gpu/command_buffer/service/context_group_unittest.cc
+++ b/gpu/command_buffer/service/context_group_unittest.cc
@@ -43,8 +43,8 @@ class ContextGroupTest : public GpuServiceTest {
     GpuServiceTest::SetUp();
     decoder_.reset(new MockGLES2Decoder());
     group_ = scoped_refptr<ContextGroup>(new ContextGroup(
-        gpu_preferences_, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
-        kBindGeneratesResource));
+        gpu_preferences_, gpu_driver_bug_workarounds_, NULL, NULL, NULL, NULL,
+        NULL, NULL, NULL, kBindGeneratesResource));
   }
 
   GpuPreferences gpu_preferences_;