content: Add DeletedGpuMemoryBuffer IPC.

content/common/gpu/gpu_memory_buffer_factory_x11_pixmap.cc

Index: content/common/gpu/gpu_memory_buffer_factory_x11_pixmap.cc
diff --git a/content/common/gpu/gpu_memory_buffer_factory_x11_pixmap.cc b/content/common/gpu/gpu_memory_buffer_factory_x11_pixmap.cc
index 04f2896fcd4dfc6591d165feb96eee102e5e92bb..95be1740c588b5c78735ac9048ee51d64ce08ae0 100644
--- a/content/common/gpu/gpu_memory_buffer_factory_x11_pixmap.cc
+++ b/content/common/gpu/gpu_memory_buffer_factory_x11_pixmap.cc
@@ -39,12 +39,10 @@ GpuMemoryBufferFactoryX11Pixmap::AcquireImageForGpuMemoryBuffer(
   X11PixmapMap::iterator it = pixmaps_.find(key);
   if (it == pixmaps_.end())
     return scoped_refptr<gfx::GLImage>();
-  XID pixmap = it->second;
-  pixmaps_.erase(it);
 
   scoped_refptr<gfx::GLImageGLX> image(
       new gfx::GLImageGLX(size, internalformat));
-  if (!image->Initialize(pixmap))
+  if (!image->Initialize(it->second))
     return scoped_refptr<gfx::GLImage>();
 
   return image;