Merge pull request #33 from wang16/mini_xslt

Disable XSLT support
Fix CrosswalkMini debug build link error

Two more files need to be procted with the disable_media_stream condition.

BUG=https://crosswalk-project.org/jira/browse/XWALK-2980
Merge pull request #34 from halton/mini_link_error

Fix CrosswalkMini debug build link error
Disable webp under gyp flag disable_webp