Switch Linux Auru ports over to POSIX SHM instead of legacy SYSV SHM.

ppapi/proxy/ppb_image_data_proxy.cc

 // Copyright (c) 2012 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 "ppapi/proxy/ppb_image_data_proxy.h"
 
 #include <string.h>  // For memcpy
 
 #include <map>
 #include <vector>
@@ skipping 413 matching lines @@
     memset(data, 0, desc_.stride * desc_.size.height);
     Unmap();
   }
 }
 
 #if !defined(OS_NACL)
 // static
 ImageHandle ImageData::NullHandle() {
 #if defined(OS_WIN)
   return NULL;
-#elif defined(OS_MACOSX) || defined(OS_ANDROID)
+#elif defined(TOOLKIT_GTK)
+  return 0;
+#else
   return ImageHandle();
-#else
-  return 0;
 #endif
 }
 
 ImageHandle ImageData::HandleFromInt(int32_t i) {
 #if defined(OS_WIN)
     return reinterpret_cast<ImageHandle>(i);
-#elif defined(OS_MACOSX) || defined(OS_ANDROID)
+#elif defined(TOOLKIT_GTK)
+    return static_cast<ImageHandle>(i);
+#else
     return ImageHandle(i, false);
-#else
-    return static_cast<ImageHandle>(i);
 #endif
 }
 #endif  // !defined(OS_NACL)
 
 // PPB_ImageData_Proxy ---------------------------------------------------------
 
 PPB_ImageData_Proxy::PPB_ImageData_Proxy(Dispatcher* dispatcher)
     : InterfaceProxy(dispatcher) {
 }
 
@@ skipping 172 matching lines @@
   // still cached in our process, the proxy still holds a reference so we can
   // remove the one the renderer just sent is. If the proxy no longer holds a
   // reference, we released everything and we should also release the one the
   // renderer just sent us.
   dispatcher()->Send(new PpapiHostMsg_PPBCore_ReleaseResource(
       API_ID_PPB_CORE, old_image_data));
 }
 
 }  // namespace proxy
 }  // namespace ppapi