Remove unused script android_webview/build/install_binary.

https://codereview.chromium.org/11109014 removed the place that called it.

Gets rid of the only caller of $SCRIPT that I can find.

BUG=142642
R=torne@chromium.org

Review URL: https://codereview.chromium.org/142703007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@246913 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 246913