[unification] Move //zircon/system/utest/sysmem to the GN build

Generated with: //scripts/unification/move_zn_element.py

scripts/unification/verify_element_move.py --reference local/initial.json:

<none>

Bug: 36139
Change-Id: Ic10e8e2fd54bc9037d5e9cd45dd6cdcd37114db7
diff --git a/build/unification/images/BUILD.gn b/build/unification/images/BUILD.gn
index 629060c0..60dffcc 100644
--- a/build/unification/images/BUILD.gn
+++ b/build/unification/images/BUILD.gn
@@ -694,7 +694,6 @@
     ":test.sys.sysinfo-test",
     ":test.sys.syslog-static-test",
     ":test.sys.syslog-test",
-    ":test.sys.sysmem-test",
     ":test.sys.sysmem-unittest",
     ":test.sys.tas5782-test",
     ":test.sys.tas5805-test",
@@ -1151,7 +1150,6 @@
     ":test.sys.sysinfo-test",
     ":test.sys.syslog-static-test",
     ":test.sys.syslog-test",
-    ":test.sys.sysmem-test",
     ":test.sys.sysmem-unittest",
     ":test.sys.tas5782-test",
     ":test.sys.tas5805-test",
@@ -2205,7 +2203,7 @@
     #":test.sys.sysinfo-test",
     #":test.sys.syslog-static-test",
     #":test.sys.syslog-test",
-    #":test.sys.sysmem-test",
+    "//zircon/system/utest/sysmem:sysmem-manifest",
     #":test.sys.sysmem-unittest",
     #":test.sys.tas5782-test",
     #":test.sys.tas5805-test",
@@ -2655,7 +2653,7 @@
     #":test.sys.sysinfo-test",
     #":test.sys.syslog-static-test",
     #":test.sys.syslog-test",
-    #":test.sys.sysmem-test",
+    "//zircon/system/utest/sysmem:sysmem-manifest",
     #":test.sys.sysmem-unittest",
     #":test.sys.tas5782-test",
     #":test.sys.tas5805-test",
diff --git a/zircon/system/utest/BUILD.gn b/zircon/system/utest/BUILD.gn
index bd3d357..07c36e6 100644
--- a/zircon/system/utest/BUILD.gn
+++ b/zircon/system/utest/BUILD.gn
@@ -237,7 +237,6 @@
       "service:test",
       "stdio",
       "sysinfo",
-      "sysmem",
       "thread-initial-state",
       "thread-safe-deleter",
       "timers",
diff --git a/zircon/system/utest/sysmem/BUILD.gn b/zircon/system/utest/sysmem/BUILD.gn
index 550e827..b64da1d 100644
--- a/zircon/system/utest/sysmem/BUILD.gn
+++ b/zircon/system/utest/sysmem/BUILD.gn
@@ -2,19 +2,39 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-zx_test("sysmem") {
+##########################################
+# Though under //zircon, this build file #
+# is meant to be used in the Fuchsia GN  #
+# build.                                 #
+# See fxb/36139.                         #
+##########################################
+
+assert(!defined(zx) || zx != "/",
+       "This file can only be used in the Fuchsia GN build.")
+
+import("//build/test.gni")
+import("//build/unification/images/migrated_manifest.gni")
+
+test("sysmem") {
+  # Dependent manifests unfortunately cannot be marked as `testonly`.
+  # Remove when converting this file to proper GN build idioms.
+  testonly = false
+  configs += [ "//build/unification/config:zircon-migrated" ]
   test_group = "sys"
   sources = [ "sysmem_tests.cc" ]
   deps = [
-    "$zx/system/fidl/fuchsia-sysinfo:c",
-    "$zx/system/fidl/fuchsia-sysmem:c",
-    "$zx/system/ulib/ddk",
-    "$zx/system/ulib/fbl:headers",
-    "$zx/system/ulib/fdio",
-    "$zx/system/ulib/fidl",
-    "$zx/system/ulib/fidl-async-2",
-    "$zx/system/ulib/unittest",
-    "$zx/system/ulib/zircon",
-    "$zx/system/ulib/zx",
+    "//zircon/public/lib/ddk",
+    "//zircon/public/lib/fbl",
+    "//zircon/public/lib/fdio",
+    "//zircon/public/lib/fidl",
+    "//zircon/public/lib/fidl-async-2",
+    "//zircon/public/lib/unittest",
+    "//zircon/public/lib/zx",
+    "//zircon/system/fidl/fuchsia-sysinfo:c",
+    "//zircon/system/fidl/fuchsia-sysmem:c",
   ]
 }
+
+migrated_manifest("sysmem-manifest") {
+  deps = [ ":sysmem" ]
+}