[jumbo] Make it one GetIdMap() instead of two.

A commit just introduced two GetIdMap functions in ui/views/cocoa,
which broke jumbo builds because in jumbo builds they end up in
the same translation unit. This patch renames them
GetIdToWidgetImplMap and GetIdToWidgetHostImplMap

Bug: 859152

TBR=ccameron@chromium.org,ellyjones@chromium.org

Change-Id: I55b4a48d3d4f97c30450fd89bb8f52f46c2cedd7
Reviewed-on: https://chromium-review.googlesource.com/1219127
Reviewed-by: Daniel Bratell <bratell@opera.com>
Commit-Queue: Daniel Bratell <bratell@opera.com>
Cr-Commit-Position: refs/heads/master@{#590257}
2 files changed