[base] Replace Contains{Key,Value} with Contains in //ppapi

This change replaces usages of base::ContainsKey() and base::ContainsValue()
with base::Contains() in //ppapi.

Reproduction:
 - sed -i 's/\bbase::ContainsKey\b/base::Contains/g'
 - sed -i 's/\bbase::ContainsValue\b/base::Contains/g'
 - git cl format

This CL was uploaded by git cl split.

R=piman@chromium.org

Bug: 970209
Change-Id: I24a62e59fe4426117b9134fa2f00f8f7625d04fb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1648228
Auto-Submit: Jan Wilken Dörrie <jdoerrie@chromium.org>
Reviewed-by: Antoine Labour <piman@chromium.org>
Commit-Queue: Antoine Labour <piman@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#666835}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 5e4490ffb7bf4e84e80747887d7b3cd557732f33
1 file changed