Adding perf test isolate and gn build target for swarming the benchmarks.

chrome/test/BUILD.gn

Index: chrome/test/BUILD.gn
diff --git a/chrome/test/BUILD.gn b/chrome/test/BUILD.gn
index 36693bef5c8c29231f17f40b71b16e3c6b1855b1..9dcd6b95c32ecc110c88364f0bb7a6ce60c6c361 100644
--- a/chrome/test/BUILD.gn
+++ b/chrome/test/BUILD.gn
@@ -1715,6 +1715,20 @@ group("telemetry_perf_unittests") {
   ]
 }
 
+group("telemetry_perf_tests") {
+  testonly = true
+  deps = [
+    "//tools/perf/:perf",
+  ]
+
+  data = [
+    # Needed for isolate script to execute.
+    "//testing/scripts/common.py",
+    "//testing/xvfb.py",
+    "//testing/scripts/run_telemetry_benchmark_as_googletest.py",
+  ]
+}
+
 js2gtest("unit_tests_js") {
   test_type = "unit"
   sources = rebase_path(