Reapply parts of 73222.
Reapply parts of 73222.

Add the ability to autogenerate GLES2 implementation as part of the build.

BUG=none
TEST=run build_gles2_cmd_buffer --output-dir=something

Review URL: http://codereview.chromium.org/6417002

git-svn-id: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@74241 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser