Fix #134707: Dynamic paint brush object movement ignored

Caused by bcfe4c34da.

The code was missing a dirty tag for the positions.

source/blender/blenkernel/intern/dynamicpaint.cc

@@ -2198,7 +2198,16 @@ Mesh *dynamicPaint_Modifier_do(
 /* Create a surface for uv image sequence format. */
 #define JITTER_SAMPLES \
   { \
-    0.0f, 0.0f, -0.2f, -0.4f, 0.2f, 0.4f, 0.4f, -0.2f, -0.4f, 0.3f, \
+      0.0f, \
+      0.0f, \
+      -0.2f, \
+      -0.4f, \
+      0.2f, \
+      0.4f, \
+      0.4f, \
+      -0.2f, \
+      -0.4f, \
+      0.3f, \
   }
 
 struct DynamicPaintCreateUVSurfaceData {
@@ -4339,6 +4348,8 @@ static bool dynamicPaint_paintMesh(Depsgraph *depsgraph,
       }
     }
 
+    mesh->tag_positions_changed();
+
     if (brush->flags & MOD_DPAINT_PROX_PROJECT && brush->collision != MOD_DPAINT_COL_VOLUME) {
       mul_v3_fl(avg_brushNor, 1.0f / float(numOfVerts));
       /* instead of null vector use positive z */