linux: implement gpu plugin

chrome/renderer/command_buffer_proxy.cc

 // Copyright (c) 2009 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 "base/logging.h"
 #include "base/process_util.h"
 #include "chrome/common/command_buffer_messages.h"
 #include "chrome/common/plugin_messages.h"
 #include "chrome/renderer/command_buffer_proxy.h"
 #include "chrome/renderer/plugin_channel_host.h"
@@ skipping 135 matching lines @@
   base::SharedMemoryHandle handle;
   size_t size;
   if (!Send(new CommandBufferMsg_GetTransferBuffer(route_id_,
                                                    id,
                                                    &handle,
                                                    &size))) {
     return Buffer();
   }
 
   // Cache the transfer buffer shared memory object client side.
+#if defined(OS_WIN)
+  // TODO(piman): Does Windows needs this version of the constructor ? It
+  // duplicates the handle, but I'm not sure why it is necessary - it was
+  // already duped by the CommandBufferStub.
   base::SharedMemory* shared_memory =
       new base::SharedMemory(handle, false, base::GetCurrentProcessHandle());
+#else
+  base::SharedMemory* shared_memory =
+      new base::SharedMemory(handle, false);
+#endif
 
   // Map the shared memory on demand.
   if (!shared_memory->memory()) {
-    if (!shared_memory->Map(shared_memory->max_size())) {
+    if (!shared_memory->Map(size)) {
       delete shared_memory;
       return Buffer();
     }
   }
 
   Buffer buffer;
   buffer.ptr = shared_memory->memory();
   buffer.size = size;
   buffer.shared_memory = shared_memory;
   transfer_buffers_[id] = buffer;
@@ skipping 32 matching lines @@
   if (Send(new CommandBufferMsg_GetErrorStatus(route_id_, &status)))
     return status;
 
   return true;
 }
 
 void CommandBufferProxy::RaiseErrorStatus() {
   // Not implemented in proxy.
   NOTREACHED();
 }