[Android] End the adb_keys file with a newline.
[Android] End the adb_keys file with a newline.

BUG=
TBR=navabi@chromium.org

Review URL: https://codereview.chromium.org/1310873002

git-svn-id: 239fca9b83025a0b6f823aeeca02ba5be3d9fd76@296407 0039d316-1c4b-4281-b951-d872f2087c98

eunchong/build,eunchong/build,eunchong/build,eunchong/build