Replace base::hash_map with std::unordered_map

base::hash_map is alias of std::unordered_map now.

I applied following command to make this CL.

$ git grep -l 'base::hash_map' | fgrep -v base/ | xargs sed -i -e 's/base::hash_map/std::unordered_set/g' -e 's/\(#include <[a-z_]*>\)/\1\n#include <unordered_map>/' -e 's/BASE_HASH_NAMESPACE/std/'
$ git cl format
$ # Added IntPairHash and replaced BASE_HASH_NAMESPACE with std in some places.

TBR: [email protected]
Bug: 576864
Change-Id: I38941d9f9bcb05ec474b8dee5230c4c5dcd2211f
Reviewed-on: https://chromium-review.googlesource.com/c/1390892
Commit-Queue: Takuto Ikuta <[email protected]>
Reviewed-by: Daniel Cheng <[email protected]>
Cr-Commit-Position: refs/heads/master@{#620124}
108 files changed