Teach PRESUBMIT.py how to run gn check for most of the mojo repo

mojo/common/BUILD.gn

Index: mojo/common/BUILD.gn
diff --git a/mojo/common/BUILD.gn b/mojo/common/BUILD.gn
index 8ac78458e34e98233493366195edf07bad885a46..fc8f53c047f0c702cd39de2823108d5ce0498a89 100644
--- a/mojo/common/BUILD.gn
+++ b/mojo/common/BUILD.gn
@@ -26,6 +26,8 @@ component("common") {
     "//base",
     "//base/third_party/dynamic_annotations",
     "//mojo/public/c/system:for_component",
+    "//mojo/public/cpp/bindings",
+    "//mojo/public/cpp/system",
     "//url",
   ]
 }
@@ -35,11 +37,13 @@ test("mojo_common_unittests") {
   deps = [
     ":common",
     "//base",
+    "//base/test:test_support",
     "//base:message_loop_tests",
     "//mojo/edk/test:run_all_unittests",
     "//mojo/edk/test:test_support",
     "//mojo/environment:chromium",
     "//mojo/public/cpp/bindings",
+    "//mojo/public/cpp/system",
     "//mojo/public/cpp/test_support:test_utils",
     "//testing/gtest",
     "//url",