Make wrapperTypeInfo static member const in bindings classes

Make wrapperTypeInfo static member const in bindings classes as it can never be
altered. This allows this member to be moved from the .data section to
.data.rel.ro, which may be shared among different library instances on Android.

objdump reports that ~600 wrapperTypeInfo members are moved by this CL.

BUG=249746

Review URL: https://codereview.chromium.org/40433002

git-svn-id: svn://svn.chromium.org/blink/trunk@160488 bbb929c8-8fbe-4397-9dbb-9b2b20218538