Refactoring of parseColumnsFilter function. ELSE block is unnecessary as IF blocks end with a return statement.
Refactoring of parseColumnsFilter function.
ELSE block is unnecessary as IF blocks end with a return statement.

Change-Id: Iaff9a78e14237721eee447010f9e8193af1b3642
Reviewed-on: https://code-review.googlesource.com/29290
Reviewed-by: kokoro <2ac7b1f3fa578934c95181d4272be0d3bca00121@google.com>
Reviewed-by: Jonathan Amsterdam <e3d3698b2ccd5955e4adf250d0785062d0f9018b@google.com>

googleapis/cloud-bigtable-cbt-cli,googleapis/cloud-bigtable-cbt-cli