Convert plugin and GPU process to brokered handle duplication.

content/common/gpu/client/command_buffer_proxy_impl.cc

Index: content/common/gpu/client/command_buffer_proxy_impl.cc
===================================================================
--- content/common/gpu/client/command_buffer_proxy_impl.cc	(revision 132263)
+++ content/common/gpu/client/command_buffer_proxy_impl.cc	(working copy)
@@ -20,6 +20,10 @@
 #include "gpu/command_buffer/common/command_buffer_shared.h"
 #include "ui/gfx/size.h"
 
+#if defined(OS_WIN)
+#include "content/common/sandbox_policy.h"
+#endif
+
 using gpu::Buffer;
 
 CommandBufferProxyImpl::CommandBufferProxyImpl(
@@ -234,7 +238,13 @@
     return -1;
 
   base::SharedMemoryHandle handle = shm->handle();
-#if defined(OS_POSIX)
+#if defined(OS_WIN)
+  // Windows needs to explicitly duplicate the handle out to another process.
+  if (!sandbox::BrokerDuplicateHandle(handle, channel_->gpu_pid(),
+                                      &handle, FILE_MAP_WRITE, 0)) {
+    return -1;
+  }
+#elif defined(OS_POSIX)
   DCHECK(!handle.auto_close);
 #endif
 
@@ -257,10 +267,20 @@
   if (last_state_.error != gpu::error::kNoError)
     return -1;
 
+  // Returns FileDescriptor with auto_close off.
+  base::SharedMemoryHandle handle = shared_memory->handle();
+#if defined(OS_WIN)
+  // Windows needs to explicitly duplicate the handle out to another process.
+  if (!sandbox::BrokerDuplicateHandle(handle, channel_->gpu_pid(),
+                                      &handle, FILE_MAP_WRITE, 0)) {
+    return -1;
+  }
+#endif
+
   int32 id;
   if (!Send(new GpuCommandBufferMsg_RegisterTransferBuffer(
       route_id_,
-      shared_memory->handle(),  // Returns FileDescriptor with auto_close off.
+      handle,
       size,
       id_request,
       &id))) {