Reland "Removes ui/platform_window/mojo as it is not used by anyone."

This is a reland of 6eb61402c1b1b4301762c6aaaea28b2921cbf4c2

Original change's description:
> Removes ui/platform_window/mojo as it is not used by anyone.
> 
> This is to remove the ref to some types under ui/base/ime/mojo, which will be removed later.
> 
> Bug: 965908
> Change-Id: I7979524066104c829b4f4e287a0ab87c9365f124
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1626055
> Reviewed-by: Dominick Ng <dominickn@chromium.org>
> Reviewed-by: Scott Violet <sky@chromium.org>
> Commit-Queue: Shu Chen <shuchen@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#662924}

Bug: 965908
Change-Id: I6bb1c6d081ce235c959cc30e53d20b57dd0e1459
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1626841
Reviewed-by: Dominick Ng <dominickn@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Shu Chen <shuchen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#663381}
diff --git a/ash/BUILD.gn b/ash/BUILD.gn
index 70b198f..674512c 100644
--- a/ash/BUILD.gn
+++ b/ash/BUILD.gn
@@ -1406,7 +1406,6 @@
     "//ui/native_theme",
     "//ui/ozone",
     "//ui/platform_window",
-    "//ui/platform_window/mojo",
     "//ui/platform_window/stub",
     "//ui/snapshot",
     "//ui/views/window/vector_icons",
diff --git a/ash/host/ash_window_tree_host_platform.cc b/ash/host/ash_window_tree_host_platform.cc
index 7c917a3..ef143bf 100644
--- a/ash/host/ash_window_tree_host_platform.cc
+++ b/ash/host/ash_window_tree_host_platform.cc
@@ -24,7 +24,6 @@
 #include "ui/gfx/geometry/rect_conversions.h"
 #include "ui/gfx/geometry/rect_f.h"
 #include "ui/gfx/transform.h"
-#include "ui/platform_window/mojo/ime_type_converters.h"
 #include "ui/platform_window/platform_ime_controller.h"
 #include "ui/platform_window/platform_window.h"
 #include "ui/platform_window/platform_window_init_properties.h"
diff --git a/content/common/render_widget_host_ns_view.mojom b/content/common/render_widget_host_ns_view.mojom
index 48c46bd..2104e7c 100644
--- a/content/common/render_widget_host_ns_view.mojom
+++ b/content/common/render_widget_host_ns_view.mojom
@@ -13,7 +13,6 @@
 import "ui/gfx/geometry/mojo/geometry.mojom";
 import "ui/gfx/mojo/ca_layer_params.mojom";
 import "ui/gfx/range/mojo/range.mojom";
-import "ui/platform_window/mojo/text_input_state.mojom";
 
 // The interface through which code in the browser process, in
 // RenderWidgetHostViewMac, sends messages to the app shim process, targeting
diff --git a/services/ws/public/mojom/BUILD.gn b/services/ws/public/mojom/BUILD.gn
index 8d53c49..f19658b 100644
--- a/services/ws/public/mojom/BUILD.gn
+++ b/services/ws/public/mojom/BUILD.gn
@@ -22,7 +22,6 @@
     "//mojo/public/mojom/base",
     "//ui/gfx/geometry/mojo",
     "//ui/gfx/mojo",
-    "//ui/platform_window/mojo:interfaces",
   ]
 
   if (is_chromeos) {
diff --git a/ui/aura/BUILD.gn b/ui/aura/BUILD.gn
index f201984..e296dc2 100644
--- a/ui/aura/BUILD.gn
+++ b/ui/aura/BUILD.gn
@@ -126,7 +126,6 @@
     "//ui/gfx/geometry",
     "//ui/gl",
     "//ui/platform_window",
-    "//ui/platform_window/mojo",
     "//ui/platform_window/stub",
   ]
 
diff --git a/ui/platform_window/mojo/BUILD.gn b/ui/platform_window/mojo/BUILD.gn
deleted file mode 100644
index b42cf4f..0000000
--- a/ui/platform_window/mojo/BUILD.gn
+++ /dev/null
@@ -1,39 +0,0 @@
-# Copyright 2015 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.
-
-import("//build/config/jumbo.gni")
-import("//mojo/public/tools/bindings/mojom.gni")
-
-# This target does NOT depend on skia. One can depend on this target to avoid
-# picking up a dependency on skia.
-jumbo_component("mojo") {
-  output_name = "mojo_ime_lib"
-
-  public_deps = [
-    "//ui/base/ime",
-  ]
-  deps = [
-    ":interfaces",
-    "//base",
-    "//ui/platform_window",
-  ]
-
-  defines = [ "MOJO_IME_IMPLEMENTATION" ]
-
-  sources = [
-    "ime_type_converters.cc",
-    "ime_type_converters.h",
-    "mojo_ime_export.h",
-  ]
-}
-
-mojom("interfaces") {
-  sources = [
-    "text_input_state.mojom",
-  ]
-
-  public_deps = [
-    "//ui/base/ime/mojo",
-  ]
-}
diff --git a/ui/platform_window/mojo/DEPS b/ui/platform_window/mojo/DEPS
deleted file mode 100644
index 1d56d19d..0000000
--- a/ui/platform_window/mojo/DEPS
+++ /dev/null
@@ -1,5 +0,0 @@
-include_rules = [
-  "+ui/base/ime/text_input_flags.h",
-  "+ui/base/ime/text_input_type.h",
-  "+ui/platform_window/text_input_state.h",
-]
diff --git a/ui/platform_window/mojo/OWNERS b/ui/platform_window/mojo/OWNERS
deleted file mode 100644
index 5d54957..0000000
--- a/ui/platform_window/mojo/OWNERS
+++ /dev/null
@@ -1,5 +0,0 @@
-per-file *_type_converter*.*=set noparent
-per-file *_type_converter*.*=file://ipc/SECURITY_OWNERS
-
-per-file *.mojom=set noparent
-per-file *.mojom=file://ipc/SECURITY_OWNERS
diff --git a/ui/platform_window/mojo/ime_type_converters.cc b/ui/platform_window/mojo/ime_type_converters.cc
deleted file mode 100644
index 9435045..0000000
--- a/ui/platform_window/mojo/ime_type_converters.cc
+++ /dev/null
@@ -1,63 +0,0 @@
-// Copyright 2015 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.
-
-#include "ui/platform_window/mojo/ime_type_converters.h"
-
-#include <stdint.h>
-
-#include "base/macros.h"
-
-namespace mojo {
-
-#define TEXT_INPUT_TYPE_ASSERT(NAME)                                    \
-  static_assert(static_cast<int32_t>(ui::mojom::TextInputType::NAME) == \
-                    static_cast<int32_t>(ui::TEXT_INPUT_TYPE_##NAME),   \
-                "TEXT_INPUT_TYPE must match")
-TEXT_INPUT_TYPE_ASSERT(NONE);
-TEXT_INPUT_TYPE_ASSERT(TEXT);
-TEXT_INPUT_TYPE_ASSERT(PASSWORD);
-TEXT_INPUT_TYPE_ASSERT(SEARCH);
-TEXT_INPUT_TYPE_ASSERT(EMAIL);
-TEXT_INPUT_TYPE_ASSERT(NUMBER);
-TEXT_INPUT_TYPE_ASSERT(TELEPHONE);
-TEXT_INPUT_TYPE_ASSERT(URL);
-TEXT_INPUT_TYPE_ASSERT(DATE);
-TEXT_INPUT_TYPE_ASSERT(DATE_TIME);
-TEXT_INPUT_TYPE_ASSERT(DATE_TIME_LOCAL);
-TEXT_INPUT_TYPE_ASSERT(MONTH);
-TEXT_INPUT_TYPE_ASSERT(TIME);
-TEXT_INPUT_TYPE_ASSERT(WEEK);
-TEXT_INPUT_TYPE_ASSERT(TEXT_AREA);
-TEXT_INPUT_TYPE_ASSERT(CONTENT_EDITABLE);
-TEXT_INPUT_TYPE_ASSERT(DATE_TIME_FIELD);
-TEXT_INPUT_TYPE_ASSERT(MAX);
-
-#define TEXT_INPUT_FLAG_ASSERT(NAME)                                    \
-  static_assert(static_cast<int32_t>(ui::mojom::TextInputFlag::NAME) == \
-                    static_cast<int32_t>(ui::TEXT_INPUT_FLAG_##NAME),   \
-                "TEXT_INPUT_FLAG must match")
-TEXT_INPUT_FLAG_ASSERT(NONE);
-TEXT_INPUT_FLAG_ASSERT(AUTOCOMPLETE_ON);
-TEXT_INPUT_FLAG_ASSERT(AUTOCOMPLETE_OFF);
-TEXT_INPUT_FLAG_ASSERT(AUTOCORRECT_ON);
-TEXT_INPUT_FLAG_ASSERT(AUTOCORRECT_OFF);
-TEXT_INPUT_FLAG_ASSERT(SPELLCHECK_ON);
-TEXT_INPUT_FLAG_ASSERT(SPELLCHECK_OFF);
-TEXT_INPUT_FLAG_ASSERT(AUTOCAPITALIZE_NONE);
-TEXT_INPUT_FLAG_ASSERT(AUTOCAPITALIZE_CHARACTERS);
-TEXT_INPUT_FLAG_ASSERT(AUTOCAPITALIZE_WORDS);
-TEXT_INPUT_FLAG_ASSERT(AUTOCAPITALIZE_SENTENCES);
-
-// static
-ui::TextInputState
-TypeConverter<ui::TextInputState, ui::mojom::TextInputStatePtr>::Convert(
-    const ui::mojom::TextInputStatePtr& input) {
-  return ui::TextInputState(
-      ConvertTo<ui::TextInputType>(input->type), input->flags,
-      input->text.has_value() ? input->text.value() : std::string(),
-      input->selection_start, input->selection_end, input->composition_start,
-      input->composition_end, input->can_compose_inline);
-}
-
-}  // namespace mojo
diff --git a/ui/platform_window/mojo/ime_type_converters.h b/ui/platform_window/mojo/ime_type_converters.h
deleted file mode 100644
index a55125d..0000000
--- a/ui/platform_window/mojo/ime_type_converters.h
+++ /dev/null
@@ -1,23 +0,0 @@
-// Copyright 2015 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.
-
-#ifndef UI_PLATFORM_WINDOW_MOJO_IME_TYPE_CONVERTERS_H_
-#define UI_PLATFORM_WINDOW_MOJO_IME_TYPE_CONVERTERS_H_
-
-#include "ui/base/ime/ime_text_span.h"
-#include "ui/platform_window/mojo/mojo_ime_export.h"
-#include "ui/platform_window/mojo/text_input_state.mojom.h"
-#include "ui/platform_window/text_input_state.h"
-
-namespace mojo {
-
-template <>
-struct MOJO_IME_EXPORT
-    TypeConverter<ui::TextInputState, ui::mojom::TextInputStatePtr> {
-  static ui::TextInputState Convert(const ui::mojom::TextInputStatePtr& input);
-};
-
-}  // namespace mojo
-
-#endif  // UI_PLATFORM_WINDOW_MOJO_IME_TYPE_CONVERTERS_H_
diff --git a/ui/platform_window/mojo/mojo_ime_export.h b/ui/platform_window/mojo/mojo_ime_export.h
deleted file mode 100644
index e616f25..0000000
--- a/ui/platform_window/mojo/mojo_ime_export.h
+++ /dev/null
@@ -1,32 +0,0 @@
-// Copyright 2015 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.
-
-#ifndef UI_PLATFORM_WINDOW_MOJO_MOJO_IME_EXPORT_H_
-#define UI_PLATFORM_WINDOW_MOJO_MOJO_IME_EXPORT_H_
-
-#if defined(COMPONENT_BUILD)
-
-#if defined(WIN32)
-
-#if defined(MOJO_IME_IMPLEMENTATION)
-#define MOJO_IME_EXPORT __declspec(dllexport)
-#else
-#define MOJO_IME_EXPORT __declspec(dllimport)
-#endif
-
-#else  // !defined(WIN32)
-
-#if defined(MOJO_IME_IMPLEMENTATION)
-#define MOJO_IME_EXPORT __attribute__((visibility("default")))
-#else
-#define MOJO_IME_EXPORT
-#endif
-
-#endif  // defined(WIN32)
-
-#else  // !defined(COMPONENT_BUILD)
-#define MOJO_IME_EXPORT
-#endif
-
-#endif  // UI_PLATFORM_WINDOW_MOJO_MOJO_IME_EXPORT_H_
diff --git a/ui/platform_window/mojo/text_input_state.mojom b/ui/platform_window/mojo/text_input_state.mojom
deleted file mode 100644
index 21767a5..0000000
--- a/ui/platform_window/mojo/text_input_state.mojom
+++ /dev/null
@@ -1,36 +0,0 @@
-// Copyright 2015 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.
-
-module ui.mojom;
-
-import "ui/base/ime/mojo/ime_types.mojom";
-
-// Text input info which is based on blink::WebTextInputInfo.
-struct TextInputState {
-  // The type of input field.
-  TextInputType type;
-
-  // The flags of the input field (autocorrect, autocomplete, etc.).
-  int32 flags;
-
-  // The value of the input field.
-  string? text;
-
-  // The cursor position of the current selection start, or the caret position
-  // if nothing is selected.
-  int32 selection_start;
-
-  // The cursor position of the current selection end, or the caret position
-  // if nothing is selected.
-  int32 selection_end;
-
-  // The start position of the current composition, or -1 if there is none.
-  int32 composition_start;
-
-  // The end position of the current composition, or -1 if there is none.
-  int32 composition_end;
-
-  // Whether or not inline composition can be performed for the current input.
-  bool can_compose_inline;
-};