Add C++ string Include to ShowGlobals.cc

This fixes a build error due to use of std::wstring.

BUG=
TBR=brucedawson@chromium.org

Change-Id: Ibb7c6f3eb856457d5b787976b826ac675117973f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1877451
Reviewed-by: Robert Liao <robliao@chromium.org>
Reviewed-by: Bruce Dawson <brucedawson@chromium.org>
Commit-Queue: Robert Liao <robliao@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#708832}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 1fb9534c7efac4b20b8dac0d5d694e6da07cb414
1 file changed