Allow android::base::ScopeGuard in STL containers This change lets android::base::ScopeGuard be useful in STL containers (e.g. std::vector<android::base::ScopeGuard<std::function<void()>>>). It also provides perfect forwarding for android::base::make_scope_guard. Bug: 34764308 Test: libbase_test Change-Id: I7d1e5494b0f0695763cff0700efdb9ec18ae85c8 Merged-In: I7d1e5494b0f0695763cff0700efdb9ec18ae85c8 (cherry picked from commit b77035b89a3e95358a1aac9e28cd61c8b256e7ae)