Internal change

PiperOrigin-RevId: 332377554

official/vision/keras_cv/ops/box_matcher.py

@@ -146,14 +146,10 @@ class BoxMatcher:
       else:
         return matches
 
-    if similarity_matrix.shape.is_fully_defined():
-      if similarity_matrix.shape.dims[0].value == 0:
-        return _match_when_rows_are_empty()
-      else:
-        return _match_when_rows_are_non_empty()
-    else:
+    num_gt_boxes = similarity_matrix.shape.as_list()[0] or tf.shape(
+        similarity_matrix)[0]
     return tf.cond(
-          pred=tf.greater(tf.shape(similarity_matrix)[0], 0),
+        pred=tf.greater(num_gt_boxes, 0),
         true_fn=_match_when_rows_are_non_empty,
         false_fn=_match_when_rows_are_empty)