Reland: Move TouchSelectionController from content to ui

ui/touch_selection/BUILD.gn

+# 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.
+
+import("//build/config/ui.gni")
+
+if (is_android) {
+  import("//build/config/android/rules.gni")
+}
+
+component("touch_selection") {
+  output_name = "ui_touch_selection"
+
+  sources = [
+    "selection_event_type.h",
+    "touch_handle.cc",
+    "touch_handle.h",
+    "touch_selection_controller.cc",
+    "touch_selection_controller.h",
+    "ui_touch_selection_export.h",
+  ]
+
+  defines = [ "UI_TOUCH_SELECTION_IMPLEMENTATION" ]
+
+  deps = [
+    "//base:base",
+    "//ui/base:base",
+    "//ui/events:events",
+    "//ui/events:gesture_detection",
+    "//ui/gfx/geometry:geometry",
+  ]
+}
+
+test("ui_touch_selection_unittests") {
+  sources = [
+    "touch_handle_unittest.cc",
+    "touch_selection_controller_unittest.cc",
+  ]
+
+  deps = [
+    ":touch_selection",
+    "//base/test:run_all_unittests",
+    "//testing/gtest:gtest",
+    "//ui/base:base",
+    "//ui/events:test_support",
+    "//ui/gfx:gfx",
+    "//ui/gfx:test_support",
+  ]
+}
+
+if (is_android) {
+  java_cpp_enum("ui_touch_selection_enums_srcjar") {
+    sources = [
+      "selection_event_type.h",
+    ]
+    outputs = [
+      "org/chromium/ui/touch_selection/SelectionEventType.java",
+    ]
+  }
+}