Rename kAvatarIconSize to be unique (browser/ui)

When building using Jumbo unnamed namespaces gets merged
and variables with the same name conflict. This happens
for the variables kAvatarIconSize in
views/profiles/dice_accounts_menu.cc and
webui/signin/user_manager_screen_handler.cc.

This commit solves the issue by renaming the variables to
something more file specific.

Bug: 773275
Change-Id: Ibb0aa4bf8c65fcdc70d5b747cccea336ab77ca9b
Reviewed-on: https://chromium-review.googlesource.com/1107708
Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Oscar Johansson <oscarj@opera.com>
Cr-Commit-Position: refs/heads/master@{#569977}
2 files changed