Moves around js bindings related classes

The js files ended up in mojo/public/bindings/js
The C++ code in mojo/bindings/js

Adds a new target with the c++, mojo_js_bindings_lib

I'm leaving the unit tests where they are for now, which is not
ideal. Will move them in a followup patch.

BUG=none
TEST=none
[email protected]
[email protected]

Review URL: https://codereview.chromium.org/189453003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@255716 0039d316-1c4b-4281-b951-d872f2087c98
23 files changed