Add chrome perf tests and sniffer to GN build.

BUILD.gn

Index: BUILD.gn
diff --git a/BUILD.gn b/BUILD.gn
index e2fdb39d5ee2ec7fa730985c109bf38fbc3b354b..eb2379ef573889b549b5173920bb8abe9035680d 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -38,6 +38,8 @@ group("root") {
     "//chrome/common",
     "//chrome/plugin",
     "//chrome/renderer",
+    "//chrome/test",
+    "//chrome/tools",
     "//chrome/utility",
     "//components:all_components",
     "//content",
@@ -205,6 +207,8 @@ group("root") {
       "//chrome/common",
       "//chrome/plugin",
       "//chrome/renderer",
+      "//chrome/test",
+      "//chrome/tools",
       "//chrome/utility",
       "//content/shell:content_shell",
       "//extensions/browser",