Reland "Organize typemaps in //mojo/ shared for Blink variant"

This is a reland of b7b4d8b4

Original change's description:
> Organize typemaps in //mojo/ shared for Blink variant
> 
> BUG=
> 
> Change-Id: Ie397047eb79a8639d5e14718f076c17376f9a252
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1619204
> Reviewed-by: Ken Rockot <rockot@google.com>
> Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
> Commit-Queue: Leon Han <leon.han@intel.com>
> Cr-Commit-Position: refs/heads/master@{#661602}

Change-Id: Ibabdc03be43e10e0a626f960c34321aa19a76c6b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1621709Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Reviewed-by: Ken Rockot <rockot@google.com>
Commit-Queue: Leon Han <leon.han@intel.com>
Cr-Commit-Position: refs/heads/master@{#662503}

mojo/public/cpp/base/BUILD.gn

@@ -34,6 +34,8 @@ component("shared_typemap_traits") {
     "big_buffer_mojom_traits.h",
     "file_info_mojom_traits.cc",
     "file_info_mojom_traits.h",
+    "file_mojom_traits.cc",
+    "file_mojom_traits.h",
     "file_path_mojom_traits.cc",
     "file_path_mojom_traits.h",
     "shared_memory_mojom_traits.cc",

mojo/public/cpp/base/file.typemap

@@ -5,9 +5,9 @@
 mojom = "//mojo/public/mojom/base/file.mojom"
 public_headers = [ "//base/files/file.h" ]
 traits_headers = [ "//mojo/public/cpp/base/file_mojom_traits.h" ]
-sources = [
-  "//mojo/public/cpp/base/file_mojom_traits.cc",
-  "//mojo/public/cpp/base/file_mojom_traits.h",
+public_deps = [
+  "//base",
+  "//mojo/public/cpp/base:shared_typemap_traits",
 ]
 
 type_mappings =

mojo/public/cpp/base/file_mojom_traits.h

@@ -12,7 +12,7 @@
 namespace mojo {
 
 template <>
-struct COMPONENT_EXPORT(MOJO_BASE_MOJOM)
+struct COMPONENT_EXPORT(MOJO_BASE_SHARED_TRAITS)
     StructTraits<mojo_base::mojom::FileDataView, base::File> {
   static bool IsNull(const base::File& file) { return !file.IsValid(); }
 

third_party/blink/public/blink_typemaps.gni

@@ -5,8 +5,14 @@
 typemaps = [
   "//gpu/ipc/common/mailbox_holder_for_blink.typemap",
   "//gpu/ipc/common/sync_token.typemap",
+  "//mojo/public/cpp/base/big_buffer.typemap",
+  "//mojo/public/cpp/base/file.typemap",
+  "//mojo/public/cpp/base/file_info.typemap",
+  "//mojo/public/cpp/base/file_path.typemap",
   "//mojo/public/cpp/base/file_error.typemap",
+  "//mojo/public/cpp/base/shared_memory.typemap",
   "//mojo/public/cpp/base/time.typemap",
+  "//mojo/public/cpp/base/unguessable_token.typemap",
   "//services/viz/public/cpp/compositing/begin_frame_args_for_blink.typemap",
   "//services/viz/public/cpp/compositing/compositor_frame_for_blink.typemap",
   "//services/viz/public/cpp/compositing/frame_sink_id.typemap",

third_party/blink/renderer/platform/mojo/big_buffer.typemap

-# 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.
-
-mojom = "//mojo/public/mojom/base/big_buffer.mojom"
-public_headers = [ "//mojo/public/cpp/base/big_buffer.h" ]
-traits_headers = [ "//mojo/public/cpp/base/big_buffer_mojom_traits.h" ]
-public_deps = [
-  "//mojo/public/cpp/base",
-  "//mojo/public/cpp/base:shared_typemap_traits",
-]
-type_mappings = [ "mojo_base.mojom.BigBuffer=mojo_base::BigBuffer[move_only]" ]

third_party/blink/renderer/platform/mojo/blink_typemaps.gni

@@ -3,20 +3,13 @@
 # found in the LICENSE file.
 
 typemaps = [
-  "//mojo/public/cpp/base/file_info.typemap",
-  "//mojo/public/cpp/base/file_path.typemap",
-  "//mojo/public/cpp/base/file_error.typemap",
-  "//mojo/public/cpp/base/shared_memory.typemap",
-  "//mojo/public/cpp/base/unguessable_token.typemap",
   "//third_party/blink/renderer/core/messaging/blink_cloneable_message.typemap",
   "//third_party/blink/renderer/core/messaging/blink_transferable_message.typemap",
   "//third_party/blink/renderer/modules/indexeddb/indexed_db_blink.typemap",
   "//third_party/blink/renderer/platform/blob/serialized_blob.typemap",
-  "//third_party/blink/renderer/platform/mojo/big_buffer.typemap",
   "//third_party/blink/renderer/platform/mojo/big_string.typemap",
   "//third_party/blink/renderer/platform/mojo/canonical_cookie.typemap",
   "//third_party/blink/renderer/platform/mojo/fetch_api_request_headers.typemap",
-  "//third_party/blink/renderer/platform/mojo/file.typemap",
   "//third_party/blink/renderer/platform/mojo/geometry.typemap",
   "//third_party/blink/renderer/platform/mojo/kurl.typemap",
   "//third_party/blink/renderer/platform/mojo/security_origin.typemap",

third_party/blink/renderer/platform/mojo/file.typemap

-# 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.
-
-mojom = "//mojo/public/mojom/base/file.mojom"
-public_headers = [ "//base/files/file.h" ]
-traits_headers = [ "//mojo/public/cpp/base/file_mojom_traits.h" ]
-deps = [
-  "//mojo/public/mojom/base",
-]
-type_mappings =
-    [ "mojo_base.mojom.File=base::File[move_only,nullable_is_same_type]" ]