[ios] Adds code to support the iOS Handoff feature.

BUG=662936

Review-Url: https://codereview.chromium.org/2484703003
Cr-Commit-Position: refs/heads/master@{#430766}
diff --git a/ios/chrome/browser/BUILD.gn b/ios/chrome/browser/BUILD.gn
index 3af212a9..eb418f19 100644
--- a/ios/chrome/browser/BUILD.gn
+++ b/ios/chrome/browser/BUILD.gn
@@ -77,6 +77,7 @@
     "//components/autofill/core/browser",
     "//components/autofill/core/common",
     "//components/gcm_driver",
+    "//components/handoff",
     "//components/keyed_service/core",
     "//components/keyed_service/ios",
     "//components/metrics",