win vs2015: fix variable shadowing warnings

win vs2015: fix variable shadowing warnings in net/base

d:\src\cr2\src\net\base\mime_util.cc(1286): warning C4456: declaration of 'extension' hides previous local declaration
d:\src\cr2\src\net\base\mime_util.cc(1278): note: see declaration of 'extension'

d:\src\cr2\src\net\base\upload_file_element_reader.cc(122): warning C4457: declaration of 'result' hides function parameter
d:\src\cr2\src\net\base\upload_file_element_reader.cc(106): note: see declaration of 'result'

d:\src\cr2\src\net\base\url_util.cc(47): warning C4457: declaration of 'value' hides function parameter
d:\src\cr2\src\net\base\url_util.cc(33): note: see declaration of 'value'

R=rdsmith@chromium.org
BUG=440500
Committed: https://crrev.com/edba32ccb3147b5bc034f44a26d5e886c72f0366
Cr-Commit-Position: refs/heads/master@{#317603}

[scottmg, 2015-02-20 05:02:06]

https://codereview.chromium.org/945713002/diff/1/net/base/url_util.cc
File net/base/url_util.cc (left):

https://codereview.chromium.org/945713002/diff/1/net/base/url_util.cc#oldcode47
net/base/url_util.cc:47: input.data() + value_range.begin, value_range.len);
this one seems a little tricky because it's shadowing a parameter, but as far as
I can see this value is never used.

[Randy Smith (Not in Mondays), 2015-02-23 14:34:50]

lgtm

[scottmg, 2015-02-23 16:38:12]

The CQ bit was checked by scottmg@chromium.org

[commit-bot: I haz the power, 2015-02-23 16:38:53]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/945713002/1

[commit-bot: I haz the power, 2015-02-23 17:33:32]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-02-23 17:34:20]

Patchset 1 (id:??) landed as
https://crrev.com/edba32ccb3147b5bc034f44a26d5e886c72f0366
Cr-Commit-Position: refs/heads/master@{#317603}