CopyOutputResult must have a working release callback when received over mojo

cc/ipc/BUILD.gn

Index: cc/ipc/BUILD.gn
diff --git a/cc/ipc/BUILD.gn b/cc/ipc/BUILD.gn
index 42eaf444d11a0eabe11071c3d90a3a392fcb9c62..0f4e8147ecb64a01085be9925d67eaa3b9212251 100644
--- a/cc/ipc/BUILD.gn
+++ b/cc/ipc/BUILD.gn
@@ -37,6 +37,15 @@ cc_component("ipc") {
   ]
 }
 
+mojom("texture_mailbox_releaser_interface") {
+  sources = [
+    "texture_mailbox_releaser.mojom",

[danakj, 2017/02/10 18:32:50]

why isn't this part of "interfaces" below?

[Saman Sami, 2017/02/10 19:10:07]

because struct traits depending on interfaces creates a cycle.

[danakj, 2017/02/10 22:51:03]

Can you leave a comment here explaining this is a helper interface used by
struct traits? And maybe put it lower in the file so people don't cargo-cult
into it as easily?

+  ]
+  public_deps = [
+    "//gpu/ipc/common:interfaces",
+  ]
+}
+
 mojom("interfaces") {
   sources = [
     "begin_frame_args.mojom",
@@ -63,6 +72,7 @@ mojom("interfaces") {
   ]
 
   public_deps = [
+    "//cc/ipc:texture_mailbox_releaser_interface",
     "//gpu/ipc/common:interfaces",
     "//mojo/common:common_custom_types",
     "//skia/public/interfaces",
@@ -130,6 +140,7 @@ cc_source_set("struct_traits") {
     ":interfaces_shared_cpp_sources",
     "//base",
     "//cc",
+    "//cc/ipc:texture_mailbox_releaser_interface",
     "//cc/surfaces:surface_id",
     "//gpu/ipc/common:struct_traits",
     "//mojo/common:struct_traits",