Introduce XGetImage() for GrabWindowSnapshot() in ChromeOS.

chrome/browser/ui/window_snapshot/window_snapshot_aura.cc

Index: chrome/browser/ui/window_snapshot/window_snapshot_aura.cc
diff --git a/chrome/browser/ui/window_snapshot/window_snapshot_aura.cc b/chrome/browser/ui/window_snapshot/window_snapshot_aura.cc
index 29a7417f1ff501866bfb1b4475a7e08eeb02a6fa..f542ad51aa371567225f23481a4fce079c956682 100644
--- a/chrome/browser/ui/window_snapshot/window_snapshot_aura.cc
+++ b/chrome/browser/ui/window_snapshot/window_snapshot_aura.cc
@@ -7,6 +7,7 @@
 #include "base/logging.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "ui/aura/window.h"
+#include "ui/aura/root_window.h"
 #include "ui/compositor/compositor.h"
 #include "ui/compositor/dip_util.h"
 #include "ui/compositor/layer.h"
@@ -18,6 +19,12 @@ namespace browser {
 bool GrabWindowSnapshot(gfx::NativeWindow window,
                         std::vector<unsigned char>* png_representation,
                         const gfx::Rect& snapshot_bounds) {
+#if defined(OS_CHROMEOS)

[Daniel Erat, 2012/05/14 23:17:40]

Should this be OS_LINUX?  I don't see anything Chrome OS-specific here.

[Jun Mukai, 2012/05/15 22:39:24]

Done.

+  // We use XGetImage() for ChromeOS for the performance reason.

[Daniel Erat, 2012/05/14 23:17:40]

nit: s/the performance reason/performance reasons/

Does Windows not have the same performance problems?

[Jun Mukai, 2012/05/15 22:39:24]

Done.

+  // See crbug.com/122720
+  return window->GetRootWindow()->GrabWindowSnapshot(
+      png_representation, snapshot_bounds);
+#else
   ui::Compositor* compositor = window->layer()->GetCompositor();
 
   gfx::Rect read_pixels_bounds = snapshot_bounds;
@@ -46,6 +53,7 @@ bool GrabWindowSnapshot(gfx::NativeWindow window,
                         std::vector<gfx::PNGCodec::Comment>(),
                         png_representation);
   return true;
+#endif
 }
 
 }  // namespace browser