android envsetup: Stop exporting (and honoring) ANDROID_SDK_VERSION.

If someone wants to use a custom android sdk version, they now need to set
the android_sdk_version gyp define instead of this env var.

(Depends on one internal change to an internal bot that currently sets the
env var: https://chrome-internal-review.googlesource.com/154255)

BUG=330631

Review URL: https://codereview.chromium.org/159463002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251354 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 251354
Fix sysroot_ld_path.sh to correctly process the included configs.

The $included_files var contains a list of paths relative to the sysroot.
However calling `ls $included_files` gives us a list of paths relative to the host system root, which is obviously wrong. We need to do `ls $root$included_files` instead.

BUG=324207
R=thestig@chromium.org
CC=sl.ostapenko@samsung.com

Review URL: https://codereview.chromium.org/163103003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251356 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 251356