Remove a bunch of NPAPI quirks and related support code

content/child/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/features.gni")
 import("//build/config/ui.gni")
 import("//content/child/child.gni")
 
 source_set("child") {
   # Only the public target should depend on this. All other targets (even
@@ skipping 75 matching lines @@
 
     if (is_mac) {
       sources -= [
         "npapi/plugin_instance_mac.mm",
         "npapi/plugin_web_event_converter_mac.h",
         "npapi/plugin_web_event_converter_mac.mm",
         "npapi/webplugin_accelerated_surface_mac.h",
         "npapi/webplugin_delegate_impl_mac.mm",
       ]
     } else if (is_win) {
-      sources -= [
-        "npapi/webplugin_delegate_impl_win.cc",
-        "npapi/webplugin_ime_win.cc",
-        "npapi/webplugin_ime_win.h",
-      ]
+      sources -= [ "npapi/webplugin_delegate_impl_win.cc" ]
     } else if (is_android) {
       sources -= [ "npapi/webplugin_delegate_impl_android.cc" ]
     }
     if (use_aura) {
       sources -= [ "npapi/webplugin_delegate_impl_aura.cc" ]
     }
   }
 
   configs += [
     "//content:content_implementation",
     "//build/config/compiler:no_size_t_to_int_warning",
   ]
 
   if (use_aura && is_mac) {
     # This file is already excluded on non-Mac.
     sources -= [ "npapi/webplugin_delegate_impl_mac.mm" ]
   }
 
   if (is_win || !use_aura) {
     sources -= [ "npapi/webplugin_delegate_impl_aura.cc" ]
   }
 }