Closes the pipe when a Binding is destroyed. This was always the intended
behavior.

Note: No tests in this CL because jamesr@ is concurrently adding
a bunch of tests in a separate CL and will test this new code there.

R=jamesr@chromium.org, jamesr

Review URL: https://codereview.chromium.org/1006653002

mojo/public/cpp/bindings/binding.h

diff --git a/mojo/public/cpp/bindings/binding.h b/mojo/public/cpp/bindings/binding.h
index f178431..a982bdb 100644
--- a/mojo/public/cpp/bindings/binding.h
+++ b/mojo/public/cpp/bindings/binding.h
@@ -101,7 +101,7 @@
   // implementation unbound.
   ~Binding() override {
     if (internal_router_) {
-      DestroyRouter();
+      Close();
     }
   }