Add GN target for building the cros VM sanity test.

The actual test binary is actually baked into the VM image. The gn
target here just builds chrome and a wrapper script around the test
runner.

Bug: 832374
Change-Id: I062c80966abb6a234511ba125cdfb5c86367d9ad
Reviewed-on: https://chromium-review.googlesource.com/1057961
Commit-Queue: Ben Pastene <bpastene@chromium.org>
Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Cr-Commit-Position: refs/heads/master@{#558459}

build/config/chromeos/rules.gni

@@ -10,11 +10,17 @@ declare_args() {
 }
 
 template("generate_vm_runner_script") {
-  _vm_image_path = "//build/cros_cache/chrome-sdk/tarballs/${cros_board}+${cros_sdk_version}+chromiumos_qemu_image.tar.xz/"
-  _qemu_dir = "//build/cros_cache/chrome-sdk/tarballs/${cros_board}+${cros_sdk_version}+app-emulation/"
+  _cache_path_prefix =
+      "//build/cros_cache/chrome-sdk/tarballs/${cros_board}+${cros_sdk_version}"
+  _vm_image_path = "${_cache_path_prefix}+chromiumos_qemu_image.tar.xz/"
+  _qemu_dir = "${_cache_path_prefix}+app-emulation/"
 
   action(target_name) {
-    forward_variables_from(invoker, [ "testonly" ])
+    forward_variables_from(invoker,
+                           [
+                             "testonly",
+                             "need_toolchain",
+                           ])
 
     script = "//build/chromeos/create_vm_test_script.py"
 
@@ -34,6 +40,9 @@ template("generate_vm_runner_script") {
       _vm_image_path,
       _qemu_dir,
     ]
+    if (defined(need_toolchain) && need_toolchain) {
+      data += [ "${_cache_path_prefix}+target_toolchain/" ]
+    }
 
     # Required arguments used at build time by the runner script generator.
     args = [
@@ -54,9 +63,13 @@ template("generate_vm_runner_script") {
         rebase_path(invoker.test_exe, root_build_dir),
         "--output-directory",
         rebase_path(root_out_dir, root_build_dir),
-        "--runtime-deps-path",
-        rebase_path(invoker.runtime_deps_file, root_build_dir),
       ]
+      if (defined(invoker.runtime_deps_file)) {
+        args += [
+          "--runtime-deps-path",
+          rebase_path(invoker.runtime_deps_file, root_build_dir),
+        ]
+      }
     }
   }
 }

chromeos/BUILD.gn

@@ -800,6 +800,38 @@ if (cros_board != "") {
   generate_vm_runner_script("cros_vm_launcher") {
     generated_script = "$root_build_dir/bin/launch_cros_vm"
   }
+
+  # The sanity test's actual binary is baked into the vm image. All we need to
+  # do is build the test wrapper and build our own browser to push to the VM
+  # before testing it.
+  generate_vm_runner_script("cros_vm_sanity_test_wrapper") {
+    test_exe = "$root_out_dir/cros_vm_sanity_test"
+    generated_script = "$root_build_dir/bin/run_cros_vm_sanity_test"
+
+    # The sanity test needs to strip down Chrome and its deps to fit it into
+    # the VM. It does so by using binutils in the toolchain. So signal that we
+    # need the toolchain in the data.
+    need_toolchain = true
+  }
+  group("cros_vm_sanity_test") {
+    testonly = true
+    write_runtime_deps = "$root_out_dir/cros_vm_sanity_test.runtime_deps"
+    data_deps = [
+      "//:chromiumos_preflight",  # Builds the browser.
+      ":cros_vm_sanity_test_wrapper",  # Builds the test wrapper.
+    ]
+
+    # The following dependencies are needed to deploy chrome to the VM. See the
+    # link for the full list:
+    # https://codesearch.chromium.org/chromium/src/third_party/chromite/lib/chrome_util.py?l=341
+    data_deps += [ "//chrome:xdg_mime" ]
+
+    # TODO(bpastene): Figure out what's generating resources/chromeos/ and
+    # declare it as a dep instead of adding the dir directly.
+    data = [
+      "$root_out_dir/resources/chromeos/",
+    ]
+  }
 }
 
 fuzzer_test("variable_expander_fuzzer") {