Split //ios/chrome/browser in multiple targets.

ios/chrome/browser/sync/sessions/BUILD.gn

Index: ios/chrome/browser/sync/sessions/BUILD.gn
diff --git a/ios/chrome/browser/sync/sessions/BUILD.gn b/ios/chrome/browser/sync/sessions/BUILD.gn
new file mode 100644
index 0000000000000000000000000000000000000000..1e666a17b58fe51ec910d4db337513b239382a2b
--- /dev/null
+++ b/ios/chrome/browser/sync/sessions/BUILD.gn
@@ -0,0 +1,22 @@
+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+source_set("sessions") {
+  sources = [
+    "ios_chrome_local_session_event_router.h",
+    "ios_chrome_local_session_event_router.mm",
+  ]
+  deps = [
+    "//base",
+    "//components/history/core/browser",
+    "//components/keyed_service/core",
+    "//components/sync",
+    "//components/sync_sessions",
+    "//ios/chrome/browser:browser_no_public_deps",
+    "//ios/chrome/browser/browser_state",
+    "//ios/chrome/browser/history",
+    "//ios/chrome/browser/sync/glue",
+    "//ios/web",
+  ]
+}