Use XDamage in Virtual Me2Me.

remoting/host/capturer_linux.cc

 // Copyright (c) 2011 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 "remoting/host/capturer.h"
 
 #include <X11/Xlib.h>
 #include <X11/Xutil.h>
 #include <X11/extensions/Xdamage.h>
 
 #include <set>
 
 #include "base/basictypes.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "remoting/host/capturer_helper.h"
 #include "remoting/host/differ.h"
 #include "remoting/host/x_server_pixel_buffer.h"
 
 namespace remoting {
 
 namespace {
 
 static const int kBytesPerPixel = 4;
 
+// Default to false, since many systems have broken XDamage support - see
+// http://crbug.com/73423.
+static bool g_should_use_x_damage = false;
+
 static bool ShouldUseXDamage() {
-  // For now, always use full-screen polling instead of the DAMAGE extension,
-  // as this extension is broken on many current systems OOTB.
-  return false;
+  return g_should_use_x_damage;
 }
 
 // A class representing a full-frame pixel buffer
 class VideoFrameBuffer {
  public:
   VideoFrameBuffer() : bytes_per_row_(0), needs_update_(true) {}
 
   void Update(Display* display, Window root_window) {
     if (needs_update_) {
       needs_update_ = false;
@@ skipping 466 matching lines @@
 // static
 Capturer* Capturer::Create() {
   CapturerLinux* capturer = new CapturerLinux();
   if (!capturer->Init()) {
     delete capturer;
     capturer = NULL;
   }
   return capturer;
 }
 
+// static
+void Capturer::EnableXDamage(bool enable) {
+  g_should_use_x_damage = enable;
+}
+
 }  // namespace remoting