Mojo: Simplify typemap usage.

mojo/public/tools/bindings/blink_bindings_configuration.gni

+# Copyright 2016 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.
+
+variant = "wtf"
+
+for_blink = true
+
+_typemaps = [

[yzshen1, 2016/04/05 17:36:14]

I thought previously you said users didn't have to add typemaps to a global list
explicitly?

[Sam McNally, 2016/04/06 07:02:53]

Typemaps don't have to be added to this file explicitly; they could be listed in
some other gni file that this one reads. The alternative would be a Python
script to scan for all the typemaps, but that would slow down gn gen; on Linux a
simple Python script to find all the .typemap files takes 3 seconds.

[yzshen1, 2016/04/06 16:00:47]

Yeah, scanning using py script seems sad.

By "they could be listed in some other gni file that this one reads", how would
the gni file look like? Could you point me to an example?

[Sam McNally, 2016/04/07 00:19:43]

I've extracted the typemap list into imported gni files.

+  "//mojo/public/cpp/bindings/tests/test_native_types_blink.typemap",
+  "//mojo/public/cpp/bindings/tests/rect_blink.typemap",
+]
+
+typemaps = []
+foreach(typemap, _typemaps) {
+  typemaps += [ read_file(typemap, "scope") ]
+}
+
+blacklist = [
+  # TODO(sammc): Remove the following once |for_blink| bindings support WTF
+  # maps. See https://crbug.com/583738.
+  "//components/mus/public/interfaces/window_manager.mojom",
+  "//components/mus/public/interfaces/window_tree.mojom",
+  "//extensions/common/api/mime_handler.mojom",
+  "//mojo/public/interfaces/bindings/tests/test_structs.mojom",
+  "//mojo/public/interfaces/bindings/tests/test_unions.mojom",
+  "//mojo/public/interfaces/bindings/tests/validation_test_interfaces.mojom",
+  "//mojo/services/catalog/public/interfaces/catalog.mojom",
+  "//mojo/shell/public/interfaces/capabilities.mojom",
+]