Add infrastructure to instantiate a helper plugin.

content/renderer/render_widget.cc

 // Copyright (c) 2012 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.
 
 #include "content/renderer/render_widget.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop.h"
 #include "base/metrics/histogram.h"
 #include "base/stl_util.h"
 #include "base/utf_string_conversions.h"
 #include "build/build_config.h"
 #include "content/common/swapped_out_messages.h"
 #include "content/common/view_messages.h"
 #include "content/public/common/content_switches.h"
 #include "content/renderer/render_process.h"
 #include "content/renderer/render_thread_impl.h"
 #include "content/renderer/renderer_webkitplatformsupport_impl.h"
 #include "ipc/ipc_sync_message.h"
 #include "skia/ext/platform_canvas.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebCursorInfo.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebHelperPlugin.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebPagePopup.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebPopupMenu.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebPopupMenuInfo.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebRange.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebScreenInfo.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebPoint.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebRect.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebSize.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebString.h"
 #include "third_party/skia/include/core/SkShader.h"
@@ skipping 107 matching lines @@
 // static
 WebWidget* RenderWidget::CreateWebWidget(RenderWidget* render_widget) {
   switch (render_widget->popup_type_) {
     case WebKit::WebPopupTypeNone:  // Nothing to create.
       break;
     case WebKit::WebPopupTypeSelect:
     case WebKit::WebPopupTypeSuggestion:
       return WebPopupMenu::create(render_widget);
     case WebKit::WebPopupTypePage:
       return WebPagePopup::create(render_widget);
+    case WebKit::WebPopupTypeHelperPlugin:

[jamesr, 2012/06/22 18:46:42]

how is this case different from a full-page plugin? why does it need a separate
popup_type_ ?

[ddorwin, 2012/06/22 19:39:19]

This is an off-screen page that instantiates a specified plugin. The intent is
that Chrome can instantiate this plugin to provide capabilities (transparent to
the web application). Thus, the term "helper plugin". Thus, it's not a full-page
plugin or a traditional pop-up.

On 2012/06/22 18:46:42, jamesr wrote:
The plugin is not visible or part of the page. It is a separate widget.
The implementation requires a separate WebWidget class (WebHelperPlugin).
WebWidgets can currently only be created by Chrome in this function using the
popup_type_ enum. As mentioned in http://webk.it/87399#c6, it might make senee
to refactor this code since popup_type_ is only used in this initialization
function.

+      return WebKit::WebHelperPlugin::create(render_widget);
     default:
       NOTREACHED();
   }
   return NULL;
 }
 
 void RenderWidget::Init(int32 opener_id) {
   DoInit(opener_id,
          RenderWidget::CreateWebWidget(this),
          new ViewHostMsg_CreateWidget(opener_id, popup_type_,
@@ skipping 1595 matching lines @@
   }
 }
 
 bool RenderWidget::WillHandleMouseEvent(const WebKit::WebMouseEvent& event) {
   return false;
 }
 
 bool RenderWidget::WebWidgetHandlesCompositorScheduling() const {
   return false;
 }