Revert "Move mojo edk into mojo/edk"

mojo/common/BUILD.gn

Index: mojo/common/BUILD.gn
diff --git a/mojo/common/BUILD.gn b/mojo/common/BUILD.gn
index a825189bf657d3b84bf0cdc82168fb899c2e429d..4e9f6f6294f72629a1e6d5fb7e6126e0482c62d2 100644
--- a/mojo/common/BUILD.gn
+++ b/mojo/common/BUILD.gn
@@ -37,7 +37,7 @@ test("mojo_common_unittests") {
     "//base",
     "//base:message_loop_tests",
     "//mojo/common/test:run_all_unittests",
-    "//mojo/edk/test:test_support",
+    "//mojo/common/test:test_support",
     "//mojo/environment:chromium",
     "//mojo/public/cpp/bindings",
     "//mojo/public/cpp/test_support:test_utils",
@@ -49,5 +49,6 @@ test("mojo_common_unittests") {
     "common_type_converters_unittest.cc",
     "handle_watcher_unittest.cc",
     "message_pump_mojo_unittest.cc",
+    "test/multiprocess_test_helper_unittest.cc",
   ]
 }