GWP-ASan: Create top-level unit test target

TBR=caitkp@chromium.org

Bug: 896019
Change-Id: I59ead55fbc258d981092c7e99d935a2a518a8921
Reviewed-on: https://chromium-review.googlesource.com/c/1324873
Commit-Queue: Vlad Tsyrklevich <vtsyrklevich@chromium.org>
Reviewed-by: Vitaly Buka <vitalybuka@chromium.org>
Cr-Commit-Position: refs/heads/master@{#606908}

components/BUILD.gn

@@ -105,6 +105,7 @@ test("components_unittests") {
     "//components/gcm_driver/crypto:unit_tests",
     "//components/google/core/browser:unit_tests",
     "//components/grpc_support/test:unit_tests",
+    "//components/gwp_asan:unit_tests",
     "//components/history/core/browser:unit_tests",
     "//components/history/core/common:unit_tests",
     "//components/image_fetcher/core:unit_tests",
@@ -339,10 +340,7 @@ test("components_unittests") {
   }
 
   if (is_win) {
-    deps += [
-      "//components/browser_watcher:unit_tests",
-      "//components/gwp_asan/common:unit_tests",
-    ]
+    deps += [ "//components/browser_watcher:unit_tests" ]
   }
 
   if (enable_basic_printing) {

components/gwp_asan/BUILD.gn

+# Copyright 2018 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("unit_tests") {
+  testonly = true
+  if (is_win) {
+    deps = [
+      "//components/gwp_asan/common:unit_tests",
+    ]
+  }
+}