Attempt to fix the ASAN build

The gn build system in Dart can't quite build with ASAN. We'll need to fix that
in the Dart repo in order to re-enable building dart_content_handler with ASAN.

TBR=jamesr@chromium.og

Review URL: https://codereview.chromium.org/861983002

mojo/BUILD.gn

diff --git a/mojo/BUILD.gn b/mojo/BUILD.gn
index 058ec85..16d9e36 100644
--- a/mojo/BUILD.gn
+++ b/mojo/BUILD.gn
@@ -75,7 +75,7 @@
     deps += [ "//mojo/edk/system:mojo_system_unittests_apk" ]
   }
 
-  if (!is_android) {
+  if (!is_android && !is_asan) {
     deps += [
       "//mojo/dart/embedder/test:dart_unittests",
       "//services/dart:dart_apptests",

services/BUILD.gn

diff --git a/services/BUILD.gn b/services/BUILD.gn
index 4cbf9ad..5ff9e73 100644
--- a/services/BUILD.gn
+++ b/services/BUILD.gn
@@ -22,7 +22,7 @@
     "//services/window_manager",
   ]
 
-  if (!is_android) {
+  if (!is_android && !is_asan) {
     deps += [ "//services/dart" ]
   }
 }