Created placeholders for MallocHooks implementation and added define DART_USE_TCMALLOC to specifiy …

runtime/bin/BUILD.gn

 # Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
 import("gypi_contents.gni")
-
-declare_args() {
-  # Whether to fall back to built-in root certificates when they cannot be
-  # verified at the operating system level.
-  dart_use_fallback_root_certificates = false
-
-  # The BUILD.gn file that we pull from chromium as part of zlib has a
-  # dependence on //base, which we don't pull in. In a standalone build of the
-  # VM, we set this to //runtime/bin/zlib where we have a BUILD.gn file without
-  # a dependence on //base.
-  dart_zlib_path = "//third_party/zlib"
-
-  # Whether to link the standalone VM against tcmalloc. The standalone build of
-  # the VM enables this only for Linux builds.
-  dart_use_tcmalloc = false
-}
-
-# TODO(zra): Remove this when Fuchsia has a root cert cache on the filesystem.
-if (defined(is_fuchsia) && is_fuchsia) {
-  dart_use_fallback_root_certificates = true
-}
+import("../runtime_args.gni")
 
 # Generate a resources.cc file for the service isolate without Observatory.
 action("gen_resources_cc") {
   visibility = [ ":*" ]  # Only targets in this file can see this.
   script = "../tools/create_resources.py"
   inputs = [
     "../tools/create_resources.py",
   ]
 
   # The path below is hard coded for the Mojo and Flutter trees. When moving
@@ skipping 546 matching lines @@
       }
     }
 
     deps = [
              ":gen_resources_cc",
              ":standalone_dart_io",
              ":libdart_builtin",
              "$dart_zlib_path",
            ] + extra_deps
 
+    defines = extra_defines
+
     if (dart_use_tcmalloc) {
       deps += [ "//third_party/tcmalloc" ]
+      defines += [ "DART_USE_TCMALLOC" ]
     }
 
-    defines = extra_defines
-
     sources = [
                 "main.cc",
                 "vmservice_impl.cc",
                 "vmservice_impl.h",
                 "$target_gen_dir/resources_gen.cc",
               ] + extra_sources
 
     include_dirs = [
       "..",
       "//third_party",
@@ skipping 194 matching lines @@
     "..:libdart",
   ]
   include_dirs = [
     "..",
     "$target_gen_dir",
   ]
   defines = [ "TESTING" ]
 
   if (dart_use_tcmalloc) {
     deps += [ "//third_party/tcmalloc" ]
+    defines += [ "DART_USE_TCMALLOC" ]
   }
 
   # The VM sources are already included in libdart, so we just want to add in
   # the tests here.
   vm_tests = rebase_path(vm_tests_list, ".", "../vm")
 
   sources = [
               "builtin_nolib.cc",
               "run_vm_tests.cc",
             ] + builtin_impl_tests_list + vm_tests
@@ skipping 45 matching lines @@
   defines = [
     # The only effect of DART_SHARED_LIB is to export the Dart API.
     "DART_SHARED_LIB",
   ]
   if (is_win) {
     libs = [ "dart.lib" ]
     abs_root_out_dir = rebase_path(root_out_dir)
     ldflags = [ "/LIBPATH:$abs_root_out_dir" ]
   }
 }