Always include |instance| & |proto| vars in Configure*Template()

Currently there's a complex test
$accessCheck or @runtimeEnabledAttributes or @normalFunctions or
$hasConstants
(Which is mostly "is the interface only attributes?".)
...determining whether to include |instance| and |proto| variables,
specifically the following block of code:
v8::Local<v8::ObjectTemplate> instance = desc->InstanceTemplate();
v8::Local<v8::ObjectTemplate> proto = desc->PrototypeTemplate();
UNUSED_PARAM(instance);
UNUSED_PARAM(proto);

This CL removes the check, always including it, hence simplifying the CGs.
It thus adds these lines to the about 300 IDL files that are just attributes
(or otherwise fit these conditions).

Is there other impact from this?

Review URL: https://codereview.chromium.org/60443007

git-svn-id: svn://svn.chromium.org/blink/trunk@161995 bbb929c8-8fbe-4397-9dbb-9b2b20218538