Disable HTTP/2 Alternative Service for different host.

net/http/http_stream_factory_impl.cc

Index: net/http/http_stream_factory_impl.cc
diff --git a/net/http/http_stream_factory_impl.cc b/net/http/http_stream_factory_impl.cc
index 9cff8316abe2414f2c9070b5cb0973c656edaef9..fb9181cd316709acfbe3464775dce2fed8aaa92d 100644
--- a/net/http/http_stream_factory_impl.cc
+++ b/net/http/http_stream_factory_impl.cc
@@ -265,6 +265,10 @@ AlternativeService HttpStreamFactoryImpl::GetAlternativeServiceForInternal(
       if (!HttpStreamFactory::spdy_enabled())
         continue;
 
+      // TODO(bnc): Re-enable when https://crbug.com/615413 is fixed.
+      if (origin.host() != alternative_service.host)
+        continue;
+
       // Cache this entry if we don't have a non-broken Alt-Svc yet.
       if (first_alternative_service.protocol ==
           UNINITIALIZED_ALTERNATE_PROTOCOL)