Add ash perftest on background blur filter.

ash/BUILD.gn

Index: ash/BUILD.gn
diff --git a/ash/BUILD.gn b/ash/BUILD.gn
index 04c1ca663216db73bd297ad84a641462b4639db9..1bd2aa6fdcf9384bae0b65c598cf4e429e9c0c85 100644
--- a/ash/BUILD.gn
+++ b/ash/BUILD.gn
@@ -1509,6 +1509,29 @@ test("ash_unittests") {
   ]
 }
 
+test("ash_perftests") {
+  sources = [
+    "perftests/ash_background_filter_blur_perftest.cc",
+    "test/ash_perftests.cc",
+    "test/ash_test_suite.cc",
+    "test/ash_test_suite.h",
+  ]
+
+  deps = [
+    "//ash/public/cpp:ash_public_cpp",
+    "//ash/test:test_support_without_content",
+    "//base/test:test_support",
+    "//cc/base",
+    "//mojo/edk/embedder:headers",
+    "//testing/gtest",
+    "//testing/perf",
+    "//ui/aura",
+    "//ui/base",
+    "//ui/compositor:test_support",
+    "//ui/gl:test_support",
+  ]
+}
+
 executable("ash_shell_with_content") {
   testonly = true
   sources = [