Resubmission of native memory allocation info surfacing in Observatory. Fixed crashing tests and st…

runtime/vm/malloc_hooks_x64.cc

Index: runtime/vm/malloc_hooks_x64.cc
diff --git a/runtime/vm/malloc_hooks_x64.cc b/runtime/vm/malloc_hooks_x64.cc
new file mode 100644
index 0000000000000000000000000000000000000000..6cca793a90f4e35da9b36cb5e68a3c5358b46429
--- /dev/null
+++ b/runtime/vm/malloc_hooks_x64.cc
@@ -0,0 +1,21 @@
+// Copyright (c) 2017, 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.
+
+#include "vm/malloc_hooks.h"
+
+#include "vm/globals.h"
+
+#if defined(TARGET_ARCH_X64)
+
+namespace dart {
+
+#if defined(DEBUG)
+const intptr_t kSkipCount = 6;
+#elif !(defined(PRODUCT) || defined(DEBUG))
+const intptr_t kSkipCount = 5;
+#endif
+
+}  // namespace dart
+
+#endif  // defined(TARGET_ARCH_X64)