Remove legacy constructor for blur draw looper.

Now that Android no longer uses the constructor, remove it, along
with the flag.

R=djsollen@google.com, reed@google.com

Author: scroggo@google.com

Review URL: https://codereview.chromium.org/299683002

git-svn-id: http://skia.googlecode.com/svn/trunk@14797 2bbb7eff-a529-9590-31e7-b0007b416f81
3 files changed