Run clang-tidy modernize-use-equals-{delete,default} on //net/proxy

See the bugs and cxx post for justification and details:
https://groups.google.com/a/chromium.org/forum/#!topic/cxx/RkOHzIK6Tq8

This change was done using clang-tidy as described here:
https://chromium.googlesource.com/chromium/src/+/lkcr/docs/clang_tidy.md

In some cases the the tool leaves behind a string of commas where it
replaced a member initializer list
(https://bugs.llvm.org/show_bug.cgi?id=35051). They were cleaned up with:
  git diff --name-only | \
    xargs sed -E -i 's/(^\s*|\)\s*):[ ,]*= default/\1 = default/'

BUG=778959,778957
This CL was uploaded by git cl split.

[email protected]

Change-Id: I480fc15a2b48369f3943661d092a4a85e0698400
Reviewed-on: https://chromium-review.googlesource.com/799596
Reviewed-by: Matt Menke <[email protected]>
Commit-Queue: Chris Watkins <[email protected]>
Cr-Commit-Position: refs/heads/master@{#521239}
21 files changed