compute_interfaces_info_overall should compute global type info.

idl_compiler always computes global type info when invoked.
However, since the information is always required to generate binding code,
interfaces_info should have the information.

BUG=
TEST=Tools/Scripts/run-bindings-tests

Review URL: https://codereview.chromium.org/580003002

git-svn-id: svn://svn.chromium.org/blink/trunk@182306 bbb929c8-8fbe-4397-9dbb-9b2b20218538