Add DIR_METADATA files to //ios/build

Generate DIR_METADATA files and remove metadata from OWNERS
files for //ios/build.

R=sdefresne@chromium.org

Bug: 1113033
Change-Id: I83aeb5ac131c5adbdfa5ade47adda727d3a1c6bc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2468714Reviewed-by: Rohit Rao <rohitrao@chromium.org>
Commit-Queue: Edward Lesmes <ehmaldonado@chromium.org>
Auto-Submit: Edward Lesmes <ehmaldonado@chromium.org>
Cr-Commit-Position: refs/heads/master@{#816781}

ios/build/DIR_METADATA

+# Metadata information for this directory.
+#
+# For more information on DIR_METADATA files, see:
+#   https://source.chromium.org/chromium/infra/infra/+/master:go/src/infra/tools/dirmd/README.md
+#
+# For the schema of this file, see Metadata message:
+#   https://source.chromium.org/chromium/infra/infra/+/master:go/src/infra/tools/dirmd/proto/dir_metadata.proto
+
+monorail {
+  component: "Infra>Client>Chrome"
+}
+team_email: "ios-directory-owners@chromium.org"
+os: IOS
\ No newline at end of file

ios/build/OWNERS

 rohitrao@chromium.org
 sdefresne@chromium.org
-
-# TEAM: ios-directory-owners@chromium.org
-# OS: iOS
-# COMPONENT: Infra>Client>Chrome

ios/build/bots/OWNERS

@@ -3,6 +3,3 @@ rohitrao@chromium.org
 sdefresne@chromium.org
 sergeyberezin@chromium.org
 smut@google.com
-
-# TEAM: ios-directory-owners@chromium.org
-# OS: iOS