Super Dev Mode: support standalone apps without precompile

Standalone, static apps hosted entirely on the Super Dev Mode
code server didn't work with -noprecompile because we didn't
copy the public resources to the stub CompileDir and because
binding properties weren't computed.

It now copies the files and generates binding properties.

Change-Id: Ib01b3783aef18e0041370067bd056f5c50339d61
Review-Link: https://gwt-review.googlesource.com/#/c/9137/
12 files changed