Add more out of line copy ctors for complex classes.

gpu/command_buffer/service/gpu_preferences.cc

Index: gpu/command_buffer/service/gpu_preferences.cc
diff --git a/gpu/command_buffer/service/gpu_preferences.cc b/gpu/command_buffer/service/gpu_preferences.cc
index 753e56c2669e130072d81fed1c978d0eec0af4ba..06bc6b41cb905b3b93b7bf2b919d9668adf47830 100644
--- a/gpu/command_buffer/service/gpu_preferences.cc
+++ b/gpu/command_buffer/service/gpu_preferences.cc
@@ -9,6 +9,8 @@ namespace gpu {
 GpuPreferences::GpuPreferences() {
 }
 
+GpuPreferences::GpuPreferences(const GpuPreferences& other) = default;
+
 GpuPreferences::~GpuPreferences() {}
 
 }  // namespace gpu