CallDescriptors::InitializeForIsolate() is no longer needed.

CallInterfaceDescriptors initialize themselves lazily. Soon we can also tear
down the CodeStubInterfaceDescriptor explicit initialization step.

R=yangguo@chromium.org

Review URL: https://codereview.chromium.org/535103002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23652 ce2b1a6d-e550-0410-aec6-3dcde31c8c00