Move renderer plugin code into a new component.

components/plugins.gypi

+# Copyright (c) 2013 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.
+
+{
+  'conditions': [
+    ['OS != "ios"', {
+  
+      'targets': [
+        {
+          'target_name': 'plugins_renderer',
+          'type': 'static_library',
+          'dependencies': [
+            '../skia/skia.gyp:skia',
+            '../third_party/re2/re2.gyp:re2',
+            '../third_party/WebKit/public/blink.gyp:blink',
+          ],
+          'include_dirs': [
+            '..',
+          ],
+          'sources': [
+            'plugins/renderer/plugin_placeholder.cc',
+            'plugins/renderer/plugin_placeholder.h',
+            'plugins/renderer/webview_plugin.cc',
+            'plugins/renderer/webview_plugin.h',
+          ],
+          'conditions' : [
+            ['OS=="android"', {
+              'sources': [
+                'plugins/renderer/mobile_youtube_plugin.cc',
+                'plugins/renderer/mobile_youtube_plugin.h',
+              ]
+            }],
+          ],
+        },
+      ]
+    }]
+  ]
+}