Fix variable shadowing and unreachable code that it caused

Fix variable shadowing and unreachable code that it caused

Change https://codereview.chromium.org/1261643004 renamed a function
parameter so that some code became unreachable. This renames that
parameter back.

R=bsalomon@google.com
BUG=skia:4169
Committed: https://skia.googlesource.com/skia/+/7b77ac100e98f1037ae907c8830b808361f211e1

[bsalomon, 2015-08-05 20:56:58]

The CQ bit was checked by bsalomon@google.com

[bsalomon, 2015-08-05 20:56:58]

lgtm

[commit-bot: I haz the power, 2015-08-05 20:57:18]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1271353003/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1271353003/1

[brucedawson, 2015-08-05 20:58:57]

This restores the behavior of GrTextureProvider::refScratchTexture to what it
was before the cleanup in https://codereview.chromium.org/1261643004.

Note that one suggestion on the bug was to delete the local variable. However
that would change the behavior to be slightly different from what it was before
- is that desirable?

[commit-bot: I haz the power, 2015-08-05 21:05:19]

Committed patchset #1 (id:1) as
https://skia.googlesource.com/skia/+/7b77ac100e98f1037ae907c8830b808361f211e1