Reland: Implement Aura side of unified touch text selection for contents

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")
 import("//testing/test.gni")
 
 if (is_android) {
   import("//build/config/android/rules.gni")
 }
@@ skipping 35 matching lines @@
 
     sources += [
       "touch_handle_drawable_aura.cc",
       "touch_handle_drawable_aura.h",
       "touch_selection_menu_runner.cc",
       "touch_selection_menu_runner.h",
     ]
   }
 }
 
+static_library("test_support") {
+  testonly = true
+
+  sources = [
+    "touch_selection_controller_test_api.cc",
+    "touch_selection_controller_test_api.h",
+  ]
+
+  deps = [
+    ":touch_selection",
+  ]
+}
+
 test("ui_touch_selection_unittests") {
   sources = [
     "longpress_drag_selector_unittest.cc",
     "touch_handle_unittest.cc",
     "touch_selection_controller_unittest.cc",
   ]
 
   deps = [
+    ":test_support",
     ":touch_selection",
     "//base/test:run_all_unittests",
     "//testing/gmock:gmock",
     "//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",
     ]
   }
   java_cpp_enum("ui_touch_handle_orientation_srcjar") {
     sources = [
       "touch_handle_orientation.h",
     ]
     outputs = [
       "org/chromium/ui/touch_selection/TouchHandleOrientation.java",
     ]
   }
 }