[Extensions UI] Add test for "pin" string when transitively-visible

Extensions can be "transitively-visible" in the toolbar, such as when
they are unpinned, but showing a popup. Add test coverage for checking
the "pin" string in the context menu during this state.

Bug: 1100412
Change-Id: I5880111fc4a31bc35cb2e49dd8846a2f919031ce
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2390951Reviewed-by: Peter Boström <pbos@chromium.org>
Commit-Queue: Devlin <rdevlin.cronin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#804099}

chrome/browser/ui/extensions/extension_action_view_controller_unittest.cc

@@ -166,6 +166,9 @@ class ExtensionActionViewControllerUnitTest
     return extension_service_;
   }
   ToolbarActionsModel* toolbar_model() { return toolbar_model_; }
+  ExtensionsContainer* container() {
+    return test_util_->GetExtensionsContainer();
+  }
   const gfx::Size& view_size() const { return view_size_; }
 
  private:
@@ -533,8 +536,19 @@ TEST_P(ExtensionsMenuExtensionActionViewControllerUnitTest,
 
   // Default state: unpinned.
   check_visibility_string(action, IDS_EXTENSIONS_PIN_TO_TOOLBAR);
+
+  // Pin the extension; re-check.
   toolbar_model()->SetActionVisibility(id, true);
   check_visibility_string(action, IDS_EXTENSIONS_UNPIN_FROM_TOOLBAR);
+
+  // Unpin the extension and ephemerally pop it out.
+  toolbar_model()->SetActionVisibility(id, false);
+  EXPECT_FALSE(container()->IsActionVisibleOnToolbar(action));
+  base::RunLoop run_loop;
+  container()->PopOutAction(action, false, run_loop.QuitClosure());
+  EXPECT_TRUE(container()->IsActionVisibleOnToolbar(action));
+  // The string should still just be "pin".
+  check_visibility_string(action, IDS_EXTENSIONS_PIN_TO_TOOLBAR);
 }
 
 class ExtensionActionViewControllerGrayscaleTest