Move core pieces of browser\renderer_host to src\content.

chrome/browser/renderer_host/render_widget_helper.h

 // Copyright (c) 2006-2008 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.
 
 #ifndef CHROME_BROWSER_RENDERER_HOST_RENDER_WIDGET_HELPER_H_
 #define CHROME_BROWSER_RENDERER_HOST_RENDER_WIDGET_HELPER_H_
 #pragma once
 
-#include <map>
-
-#include "app/surface/transport_dib.h"
-#include "base/atomic_sequence_num.h"
-#include "base/hash_tables.h"
-#include "base/process.h"
-#include "base/ref_counted.h"
-#include "base/synchronization/lock.h"
-#include "base/synchronization/waitable_event.h"
-#include "chrome/common/window_container_type.h"
-#include "third_party/WebKit/Source/WebKit/chromium/public/WebPopupType.h"
-
-namespace IPC {
-class Message;
-}
-
-namespace base {
-class TimeDelta;
-}
-
-class ResourceDispatcherHost;
-struct ViewHostMsg_CreateWindow_Params;
-struct ViewMsg_ClosePage_Params;
-
-
-// Instantiated per RenderProcessHost to provide various optimizations on
-// behalf of a RenderWidgetHost.  This class bridges between the IO thread
-// where the RenderProcessHost's MessageFilter lives and the UI thread where
-// the RenderWidgetHost lives.
-//
-//
-// OPTIMIZED RESIZE
-//
-//   RenderWidgetHelper is used to implement optimized resize.  When the
-//   RenderWidgetHost is resized, it sends a Resize message to its RenderWidget
-//   counterpart in the renderer process.  The RenderWidget generates a
-//   UpdateRect message in response to the Resize message, and it sets the
-//   IS_RESIZE_ACK flag in the UpdateRect message to true.
-//
-//   Back in the browser process, when the RenderProcessHost's MessageFilter
-//   sees a UpdateRect message, it directs it to the RenderWidgetHelper by
-//   calling the DidReceiveUpdateMsg method.  That method stores the data for
-//   the UpdateRect message in a map, where it can be directly accessed by the
-//   RenderWidgetHost on the UI thread during a call to RenderWidgetHost's
-//   GetBackingStore method.
-//
-//   When the RenderWidgetHost's GetBackingStore method is called, it first
-//   checks to see if it is waiting for a resize ack.  If it is, then it calls
-//   the RenderWidgetHelper's WaitForUpdateMsg to check if there is already a
-//   resulting UpdateRect message (or to wait a short amount of time for one to
-//   arrive).  The main goal of this mechanism is to short-cut the usual way in
-//   which IPC messages are proxied over to the UI thread via InvokeLater.
-//   This approach is necessary since window resize is followed up immediately
-//   by a request to repaint the window.
-//
-//
-// OPTIMIZED TAB SWITCHING
-//
-//   When a RenderWidgetHost is in a background tab, it is flagged as hidden.
-//   This causes the corresponding RenderWidget to stop sending UpdateRect
-//   messages. The RenderWidgetHost also discards its backingstore when it is
-//   hidden, which helps free up memory.  As a result, when a RenderWidgetHost
-//   is restored, it can be momentarily without a backingstore.  (Restoring a
-//   RenderWidgetHost results in a WasRestored message being sent to the
-//   RenderWidget, which triggers a full UpdateRect message.)  This can lead to
-//   an observed rendering glitch as the TabContents will just have to fill
-//   white overtop the RenderWidgetHost until the RenderWidgetHost receives a
-//   UpdateRect message to refresh its backingstore.
-//
-//   To avoid this 'white flash', the RenderWidgetHost again makes use of the
-//   RenderWidgetHelper's WaitForUpdateMsg method.  When the RenderWidgetHost's
-//   GetBackingStore method is called, it will call WaitForUpdateMsg if it has
-//   no backingstore.
-//
-// TRANSPORT DIB CREATION
-//
-//   On some platforms (currently the Mac) the renderer cannot create transport
-//   DIBs because of sandbox limitations. Thus, it has to make synchronous IPCs
-//   to the browser for them. Since these requests are synchronous, they cannot
-//   terminate on the UI thread. Thus, in this case, this object performs the
-//   allocation and maintains the set of allocated transport DIBs which the
-//   renderers can refer to.
-//
-class RenderWidgetHelper
-    : public base::RefCountedThreadSafe<RenderWidgetHelper> {
- public:
-  RenderWidgetHelper();
-
-  void Init(int render_process_id,
-            ResourceDispatcherHost* resource_dispatcher_host);
-
-  // Gets the next available routing id.  This is thread safe.
-  int GetNextRoutingID();
-
-
-  // UI THREAD ONLY -----------------------------------------------------------
-
-  // These three functions provide the backend implementation of the
-  // corresponding functions in RenderProcessHost. See those declarations
-  // for documentation.
-  void CancelResourceRequests(int render_widget_id);
-  void CrossSiteClosePageACK(const ViewMsg_ClosePage_Params& params);
-  bool WaitForUpdateMsg(int render_widget_id,
-                        const base::TimeDelta& max_delay,
-                        IPC::Message* msg);
-
-#if defined(OS_MACOSX)
-  // Given the id of a transport DIB, return a mapping to it or NULL on error.
-  TransportDIB* MapTransportDIB(TransportDIB::Id dib_id);
-#endif
-
-
-  // IO THREAD ONLY -----------------------------------------------------------
-
-  // Called on the IO thread when a UpdateRect message is received.
-  void DidReceiveUpdateMsg(const IPC::Message& msg);
-
-  void CreateNewWindow(const ViewHostMsg_CreateWindow_Params& params,
-                       base::ProcessHandle render_process,
-                       int* route_id);
-  void CreateNewWidget(int opener_id,
-                       WebKit::WebPopupType popup_type,
-                       int* route_id);
-  void CreateNewFullscreenWidget(int opener_id, int* route_id);
-
-#if defined(OS_MACOSX)
-  // Called on the IO thread to handle the allocation of a TransportDIB.  If
-  // |cache_in_browser| is |true|, then a copy of the shmem is kept by the
-  // browser, and it is the caller's repsonsibility to call
-  // FreeTransportDIB().  In all cases, the caller is responsible for deleting
-  // the resulting TransportDIB.
-  void AllocTransportDIB(size_t size,
-                         bool cache_in_browser,
-                         TransportDIB::Handle* result);
-
-  // Called on the IO thread to handle the freeing of a transport DIB
-  void FreeTransportDIB(TransportDIB::Id dib_id);
-#endif
-
- private:
-  // A class used to proxy a paint message.  PaintMsgProxy objects are created
-  // on the IO thread and destroyed on the UI thread.
-  class UpdateMsgProxy;
-  friend class UpdateMsgProxy;
-  friend class base::RefCountedThreadSafe<RenderWidgetHelper>;
-
-  // Map from render_widget_id to live PaintMsgProxy instance.
-  typedef base::hash_map<int, UpdateMsgProxy*> UpdateMsgProxyMap;
-
-  ~RenderWidgetHelper();
-
-  // Called on the UI thread to discard a paint message.
-  void OnDiscardUpdateMsg(UpdateMsgProxy* proxy);
-
-  // Called on the UI thread to dispatch a paint message if necessary.
-  void OnDispatchUpdateMsg(UpdateMsgProxy* proxy);
-
-  // Called on the UI thread to finish creating a window.
-  void OnCreateWindowOnUI(const ViewHostMsg_CreateWindow_Params& params,
-                          int route_id);
-
-  // Called on the IO thread after a window was created on the UI thread.
-  void OnCreateWindowOnIO(int route_id);
-
-  // Called on the UI thread to finish creating a widget.
-  void OnCreateWidgetOnUI(int opener_id,
-                          int route_id,
-                          WebKit::WebPopupType popup_type);
-
-  // Called on the UI thread to create a fullscreen widget.
-  void OnCreateFullscreenWidgetOnUI(int opener_id, int route_id);
-
-  // Called on the IO thread to cancel resource requests for the render widget.
-  void OnCancelResourceRequests(int render_widget_id);
-
-  // Called on the IO thread to resume a cross-site response.
-  void OnCrossSiteClosePageACK(const ViewMsg_ClosePage_Params& params);
-
-#if defined(OS_MACOSX)
-  // Called on destruction to release all allocated transport DIBs
-  void ClearAllocatedDIBs();
-
-  // On OSX we keep file descriptors to all the allocated DIBs around until
-  // the renderer frees them.
-  base::Lock allocated_dibs_lock_;
-  std::map<TransportDIB::Id, int> allocated_dibs_;
-#endif
-
-  // A map of live paint messages.  Must hold pending_paints_lock_ to access.
-  // The UpdateMsgProxy objects are not owned by this map.  (See UpdateMsgProxy
-  // for details about how the lifetime of instances are managed.)
-  UpdateMsgProxyMap pending_paints_;
-  base::Lock pending_paints_lock_;
-
-  int render_process_id_;
-
-  // Event used to implement WaitForUpdateMsg.
-  base::WaitableEvent event_;
-
-  // The next routing id to use.
-  base::AtomicSequenceNumber next_routing_id_;
-
-  ResourceDispatcherHost* resource_dispatcher_host_;
-
-  DISALLOW_COPY_AND_ASSIGN(RenderWidgetHelper);
-};
+// TODO(jam): remove this file when all files have been converted.
+#include "content/browser/renderer_host/render_widget_helper.h"
 
 #endif  // CHROME_BROWSER_RENDERER_HOST_RENDER_WIDGET_HELPER_H_