GPU: Fix NULL gpu::Buffer dereference.

content/renderer/pepper/ppb_graphics_3d_impl.cc

Index: content/renderer/pepper/ppb_graphics_3d_impl.cc
diff --git a/content/renderer/pepper/ppb_graphics_3d_impl.cc b/content/renderer/pepper/ppb_graphics_3d_impl.cc
index 18a8e90e0b63d61478acecaa2cfed2d7056d0f6a..1ba14bc3a8cd480d3eff2a2bfaeaaf2a34a46174 100644
--- a/content/renderer/pepper/ppb_graphics_3d_impl.cc
+++ b/content/renderer/pepper/ppb_graphics_3d_impl.cc
@@ -38,20 +38,19 @@ namespace {
 const int32 kCommandBufferSize = 1024 * 1024;
 const int32 kTransferBufferSize = 1024 * 1024;
 
-PP_Bool ShmToHandle(base::SharedMemory* shm,
-                    size_t size,
+PP_Bool BufferToHandle(scoped_refptr<gpu::Buffer> buffer,
                     int* shm_handle,
                     uint32_t* shm_size) {
-  if (!shm || !shm_handle || !shm_size)
+  if (!buffer || !shm_handle || !shm_size)
     return PP_FALSE;
 #if defined(OS_POSIX)
-  *shm_handle = shm->handle().fd;
+  *shm_handle = buffer->shared_memory()->handle().fd;
 #elif defined(OS_WIN)
-  *shm_handle = reinterpret_cast<int>(shm->handle());
+  *shm_handle = reinterpret_cast<int>(buffer->shared_memory()->handle());
 #else
   #error "Platform not supported."
 #endif
-  *shm_size = size;
+  *shm_size = buffer->size();
   return PP_TRUE;
 }
 
@@ -128,8 +127,7 @@ PP_Bool PPB_Graphics3D_Impl::GetTransferBuffer(int32_t id,
                                                int* shm_handle,
                                                uint32_t* shm_size) {
   scoped_refptr<gpu::Buffer> buffer = GetCommandBuffer()->GetTransferBuffer(id);
-  return ShmToHandle(
-      buffer->shared_memory(), buffer->size(), shm_handle, shm_size);
+  return BufferToHandle(buffer, shm_handle, shm_size);
 }
 
 PP_Bool PPB_Graphics3D_Impl::Flush(int32_t put_offset) {