Remove non-chromeos support from src/ash BUILD.gn files

Ash only ships on Chrome OS, so simplify our BUILD.gn files by removing
all the is_win and is_chromeos conditionals.

TODO: ash/resources/BUILD.gn. Right now chrome/browser/ui has a dependency
on ash resources for aura builds on all platforms.

BUG=666776
TEST=bots

Review-Url: https://codereview.chromium.org/2559713003
Cr-Commit-Position: refs/heads/master@{#437408}
diff --git a/ash/test/BUILD.gn b/ash/test/BUILD.gn
index 02de42f..d90861d7 100644
--- a/ash/test/BUILD.gn
+++ b/ash/test/BUILD.gn
@@ -68,6 +68,11 @@
   testonly = true
   visibility = [ ":*" ]
   sources = [
+    # TODO(jamescook): Move these files into ash/test.
+    "../laser/laser_pointer_controller_test_api.cc",
+    "../laser/laser_pointer_controller_test_api.h",
+    "../laser/laser_pointer_points_test_api.cc",
+    "../laser/laser_pointer_points_test_api.h",
     "../shell/toplevel_window.cc",
     "../shell/toplevel_window.h",
     "ash_md_test_base.cc",
@@ -121,6 +126,8 @@
     "test_system_tray_item.h",
     "test_wallpaper_delegate.cc",
     "test_wallpaper_delegate.h",
+    "tray_cast_test_api.cc",
+    "tray_cast_test_api.h",
     "ui_controls_factory_ash.cc",
     "ui_controls_factory_ash.h",
     "user_metrics_recorder_test_api.cc",
@@ -139,6 +146,7 @@
     "//ash/resources",
     "//base:i18n",
     "//base/test:test_support",
+    "//chromeos",
     "//components/signin/core/account_id",
     "//components/user_manager:user_manager",
     "//device/bluetooth",
@@ -152,6 +160,7 @@
     "//ui/aura:test_support",
     "//ui/base:test_support",
     "//ui/compositor:test_support",
+    "//ui/display",
     "//ui/display/types",
     "//ui/events:events_base",
     "//ui/events:test_support",
@@ -165,29 +174,9 @@
     "//ui/wm",
   ]
 
-  if (is_win) {
-    deps += [ "//ui/platform_window/win" ]
-  }
-
   if (use_x11) {
     deps += [ "//ui/gfx/x" ]
   }
-
-  if (is_chromeos) {
-    deps += [
-      "//chromeos",
-      "//ui/display",
-    ]
-
-    sources += [
-      "../laser/laser_pointer_controller_test_api.cc",
-      "../laser/laser_pointer_controller_test_api.h",
-      "../laser/laser_pointer_points_test_api.cc",
-      "../laser/laser_pointer_points_test_api.h",
-      "tray_cast_test_api.cc",
-      "tray_cast_test_api.h",
-    ]
-  }
 }
 
 static_library("interactive_ui_test_support") {