Plugin Power Saver: Make PepperPluginInstanceThrottler interface public.

content/public/renderer/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("//content/renderer/renderer.gni")
 
 # See //content/BUILD.gn for how this works.
 group("renderer") {
   if (is_component_build) {
@@ skipping 32 matching lines @@
     # include headers from each other.
     "//content/renderer",
   ]
 
   if (enable_webrtc) {
     sources +=
         rebase_path(content_renderer_gypi_values.public_renderer_webrtc_sources,
                     ".",
                     "//content")
   }
+
+  if (enable_plugins) {
+    sources +=
+        rebase_path(content_renderer_gypi_values.public_renderer_plugin_sources,
+                    ".",
+                    "//content")
+  }
 }