Componentize safe_browsing [1]: create component, move messages, constants and switches.

components/safe_browsing/common/BUILD.gn

Index: components/safe_browsing/common/BUILD.gn
diff --git a/components/safe_browsing/common/BUILD.gn b/components/safe_browsing/common/BUILD.gn
new file mode 100644
index 0000000000000000000000000000000000000000..47587637f13f2839eeedec9b9bce28469043e27b
--- /dev/null
+++ b/components/safe_browsing/common/BUILD.gn
@@ -0,0 +1,21 @@
+# 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("common") {
+  sources = [
+    "safebrowsing_constants.cc",
+    "safebrowsing_constants.h",
+    "safebrowsing_message_generator.cc",
+    "safebrowsing_message_generator.h",
+    "safebrowsing_messages.h",
+    "safebrowsing_switches.cc",
+    "safebrowsing_switches.h",
+  ]
+
+  deps = [
+    "//base",
+    "//ipc",
+    "//url/ipc:url_ipc",
+  ]
+}