[Emoji Panel] Enable by default on Windows

Bug: 842014
Change-Id: Ie645e71c03c71fb7b7ddd7550128eb43bec3bc07
Reviewed-on: https://chromium-review.googlesource.com/1159190Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Mathieu Perreault <mathp@chromium.org>
Cr-Commit-Position: refs/heads/master@{#579996}

ui/base/ui_base_features.cc

@@ -16,7 +16,7 @@ namespace features {
 // text areas.
 const base::Feature kEnableEmojiContextMenu {
   "EnableEmojiContextMenu",
-#if defined(OS_MACOSX)
+#if defined(OS_MACOSX) || defined(OS_WIN)
       base::FEATURE_ENABLED_BY_DEFAULT
 #else
       base::FEATURE_DISABLED_BY_DEFAULT