[libfuzzer] store custom options in .GN build target instead of a separate file.

media/test/BUILD.gn

 # Copyright 2014 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.
 
 import("//media/media_options.gni")
 import("//testing/libfuzzer/fuzzer_test.gni")
 
 source_set("pipeline_integration_test_base") {
   testonly = true
 
@@ skipping 112 matching lines @@
     "//base",
     "//media",
     "//media/test:pipeline_integration_test_base",
 
     # TODO(dalecurtis): Required since the gmock header is included in the
     # header for pipeline_integration_test_base.h.  This should be
     # moved into the .cc file to avoid the extra dependency here.
     "//testing/gmock",
     "//ui/gfx:test_support",
   ]
-  libfuzzer_options = "media_pipeline_integration_fuzzer.options"
+
+  # This is done to avoid DEATH of ASan with "Thread limit exceeded" error.
+  libfuzzer_options = [ "runs=500000" ]
 }