Bust object term cache in wp_remove_object_terms().

Props tszming.
Fixes #34338.

git-svn-id: https://develop.svn.wordpress.org/trunk@35268 602fd350-edb4-49c9-b593-d223f7449a82

tests/phpunit/tests/term/wpRemoveObjectTerms.php

@@ -0,0 +1,24 @@
+<?php
+
+/**
+ * @group taxonomy
+ */
+class Tests_Term_WpRemoveObjectTerms extends WP_UnitTestCase {
+	/**
+	 * @ticket 34338
+	 */
+	public function test_removal_should_delete_object_relationship_cache() {
+		register_taxonomy( 'wptests_tax', 'post' );
+		$p = self::factory()->post->create();
+		$t = self::factory()->term->create( array( 'taxonomy' => 'wptests_tax' ) );
+
+		wp_set_object_terms( $p, $t, 'wptests_tax' );
+
+		// Pollute the cache.
+		get_the_terms( $p, 'wptests_tax' );
+
+		wp_remove_object_terms( $p, $t, 'wptests_tax' );
+
+		$this->assertFalse( get_the_terms( $p, 'wptests_tax' ) );
+	}
+}