impl window self
fix indent & name
Fix use of display().to_str in find_tests
auto merge of #1273 : sammykim/servo/issue-1197, r=jdm

Fix #1197
auto merge of #1219 : ksh8281/servo/impl_window_self, r=jdm

in order to Implement window.self
#868
Integrate 'BoxModel' into 'RenderBoxBase'. (#1257)