Fix failure of reading zero-byte files on Drive via StreamReader.

HttpByteRange by its nature represents ranges in inclusive format.
We should avoid using it during computation that might involve
empty ranges. In the old code, [0-*].ComputeBounds(0) was failing.

BUG=329328

Review URL: https://codereview.chromium.org/93883006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@242063 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 242063