Fix: Vector Blur node produce wrong output sometimes

The Vector Blur node sometimes produces wrong output. That's because no
proper memory barriers existed for the SSBO written to by the velocity
dilation pass, so ensure a proper barrier exist.

source/blender/nodes/composite/nodes/node_composite_vec_blur.cc

@@ -15,6 +15,7 @@
 
 #include "GPU_compute.hh"
 #include "GPU_shader.hh"
+#include "GPU_state.hh"
 #include "GPU_storage_buffer.hh"
 #include "GPU_vertex_buffer.hh"
 
@@ -172,6 +173,7 @@ class VectorBlurOperation : public NodeOperation {
 
     max_tile_velocity.bind_as_texture(shader, "max_velocity_tx");
 
+    GPU_memory_barrier(GPU_BARRIER_SHADER_STORAGE);
     const int slot = GPU_shader_get_ssbo_binding(shader, "tile_indirection_buf");
     GPU_storagebuf_bind(tile_indirection_buffer, slot);