[Editor] Unselect correctly removed editors

- After undoing a deletion of several editors, they appeared to be selected (they had a red border)
when in fact they were not, consequently, this patch aims to remove the selectedEditor class when
an editor is removed;
- Add a test with some ink editors.

test/integration/ink_editor_spec.js

@@ -0,0 +1,78 @@
+/* Copyright 2022 Mozilla Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+const {
+  closePages,
+  getSelectedEditors,
+  loadAndWait,
+} = require("./test_utils.js");
+
+describe("Editor", () => {
+  describe("Ink", () => {
+    let pages;
+
+    beforeAll(async () => {
+      pages = await loadAndWait("tracemonkey.pdf", ".annotationEditorLayer");
+    });
+
+    afterAll(async () => {
+      await closePages(pages);
+    });
+
+    it("must draw, undo a deletion and check that the editors are not selected", async () => {
+      await Promise.all(
+        pages.map(async ([browserName, page]) => {
+          await page.click("#editorInk");
+
+          const rect = await page.$eval(".annotationEditorLayer", el => {
+            // With Chrome something is wrong when serializing a DomRect,
+            // hence we extract the values and just return them.
+            const { x, y } = el.getBoundingClientRect();
+            return { x, y };
+          });
+
+          for (let i = 0; i < 3; i++) {
+            const x = rect.x + 100 + i * 100;
+            const y = rect.y + 100 + i * 100;
+            await page.mouse.move(x, y);
+            await page.mouse.down();
+            await page.mouse.move(x + 50, y + 50);
+            await page.mouse.up();
+
+            await page.keyboard.press("Escape");
+          }
+
+          await page.keyboard.down("Control");
+          await page.keyboard.press("a");
+          await page.keyboard.up("Control");
+
+          expect(await getSelectedEditors(page))
+            .withContext(`In ${browserName}`)
+            .toEqual([0, 2, 3]);
+
+          await page.keyboard.press("Backspace");
+
+          await page.keyboard.down("Control");
+          await page.keyboard.press("z");
+          await page.keyboard.up("Control");
+
+          expect(await getSelectedEditors(page))
+            .withContext(`In ${browserName}`)
+            .toEqual([]);
+        })
+      );
+    });
+  });
+});