Fix texture space not updating in edit mode.

source/blender/blenkernel/intern/mesh.c

@@ -876,7 +876,10 @@ void BKE_mesh_boundbox_calc(Mesh *me, float r_loc[3], float r_size[3])
 	if (!r_size) r_size = msize;
 
 	INIT_MINMAX(min, max);
-	if (!BKE_mesh_minmax(me, min, max)) {
+	if (!(me->edit_btmesh ?
+	    BM_mesh_minmax(me->edit_btmesh->bm, min, max) :
+	    BKE_mesh_minmax(me, min, max)))
+	{
 		min[0] = min[1] = min[2] = -1.0f;
 		max[0] = max[1] = max[2] = 1.0f;
 	}

source/blender/bmesh/intern/bmesh_mesh.c

@@ -2499,3 +2499,18 @@ void BM_mesh_toolflags_set(BMesh *bm, bool use_toolflags)
 
 	bm->use_toolflags = use_toolflags;
 }
+
+/**
+ * Calculate the minimum and maximum coordinates of the box that encompasses this mesh.
+ */
+bool BM_mesh_minmax(BMesh *bm, float r_min[3], float r_max[3])
+{
+	BMIter iter;
+	BMVert *v;
+
+	BM_ITER_MESH(v, &iter, bm, BM_VERTS_OF_MESH) {
+		minmax_v3v3_v3(r_min, r_max, v->co);
+	}
+
+	return (bm->totvert != 0);
+}

source/blender/bmesh/intern/bmesh_mesh.h

@@ -132,6 +132,8 @@ void BM_mesh_rebuild(
         BMesh *bm, const struct BMeshCreateParams *params,
         struct BLI_mempool *vpool, struct BLI_mempool *epool, struct BLI_mempool *lpool, struct BLI_mempool *fpool);
 
+bool BM_mesh_minmax(BMesh *bm, float r_min[3], float r_max[3]);
+
 typedef struct BMAllocTemplate {
 	int totvert, totedge, totloop, totface;
 } BMAllocTemplate;