[remoting] Add missing //base dependency to //remoting/ios/domain

//remoting/ios/domain uses classes from base but never declares
dependency in BUILD.gn, so building it with a clean target directory
will fail but rebuilding it will succeed.

This CL fixes the issue by adding the missing dependency.

Bug: 968845
Change-Id: I28655be4d710e0d8b124650808f9bbf4c41dede6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1637663
Auto-Submit: Yuwei Huang <yuweih@chromium.org>
Commit-Queue: Joe Downing <joedow@chromium.org>
Reviewed-by: Joe Downing <joedow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#665018}

remoting/ios/domain/BUILD.gn

@@ -19,6 +19,7 @@ source_set("domain") {
   ]
 
   deps = [
+    "//base",
     "//remoting/proto/remoting/v1:directory_proto",
   ]