Add build target for inputview.

third_party/google_input_tools/closure.gni

+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+template("build_closure") {
+  assert(defined(invoker.sources))
+  assert(defined(invoker.target))
+  action_name = target_name + "_js_gen"
+  action(action_name) {
+    script = "//third_party/google_input_tools/builder.py"
+    sources = invoker.sources
+    outputs = [invoker.target]
+    args = ["--target",
+            rebase_path(invoker.target, root_build_dir)]
+    if(defined(invoker.json_file)) {
+      # Optionally parse list of sources from a json file. Useful when the list
+      # is sufficiently long to create problems with length restrictions on the
+      # command line.
+      assert(defined(invoker.json_sources))
+      args += ["--json_file",
+               rebase_path(invoker.json_file, root_build_dir),
+               "--json_sources",
+               invoker.json_sources]
+    } else {
+      # If the number of source files is short, they can be directly extracted
+      # from the command line.
+      args += ["--sources"] + sources
+    }
+    if(defined(invoker.path)) {
+      args += ["--path", invoker.path]
+    }
+  }
+  group(target_name) {
+    deps = [ ":$action_name" ]
+  }
+}