Update Linux to use scoped_refptr<T>::get() rather than implicit "operator T*"

gpu/command_buffer/service/framebuffer_manager.cc

Index: gpu/command_buffer/service/framebuffer_manager.cc
diff --git a/gpu/command_buffer/service/framebuffer_manager.cc b/gpu/command_buffer/service/framebuffer_manager.cc
index 732bb7bcee9a2b17450fed3b3faad3776e154825..9a0276e78f056c12951216624ef425934f54f740 100644
--- a/gpu/command_buffer/service/framebuffer_manager.cc
+++ b/gpu/command_buffer/service/framebuffer_manager.cc
@@ -515,7 +515,7 @@ void Framebuffer::UnbindTexture(
 Framebuffer* FramebufferManager::GetFramebuffer(
     GLuint client_id) {
   FramebufferMap::iterator it = framebuffers_.find(client_id);
-  return it != framebuffers_.end() ? it->second : NULL;
+  return it != framebuffers_.end() ? it->second.get() : NULL;
 }
 
 void FramebufferManager::RemoveFramebuffer(GLuint client_id) {