Update GN build files for Mojo roll

runtime/lib/profiler_sources.gypi

Index: runtime/lib/profiler_sources.gypi
diff --git a/sdk/lib/developer/developer_sources.gypi b/runtime/lib/profiler_sources.gypi
similarity index 65%
copy from sdk/lib/developer/developer_sources.gypi
copy to runtime/lib/profiler_sources.gypi
index adbaea9f249951d2e7a78e080a3cefcfd8872de5..9175427107a3e4c8ffcb9d65e9a7d2c5ebb33ba4 100644
--- a/sdk/lib/developer/developer_sources.gypi
+++ b/runtime/lib/profiler_sources.gypi
@@ -2,10 +2,11 @@
 # 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.
 
+# Sources list to keep vm/BUILD.gn generate_core_libraries happy.
+
 {
   'sources': [
-    'developer.dart',
-    'profiler.dart',
-    # The above file needs to be first if additional parts are added to the lib.
+    'empty_source.dart'
   ],
 }
+