Fix methods visibility in arc accessibility classes

Some member functions are unnecessarily declared as protected, and they
should be private.

Also this CL fixes a lambda function from by-copy capture to by-reference
capture.

Bug: None
Test: unit_tests --gtest_filter="AXTreeSourceArcTest.*:ArcAccessibilityHelperBridgeTest.*"
Change-Id: I183174a922b6d57ea3b41a04053785b936b655b8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1850687
Commit-Queue: Hiroki Sato <hirokisato@chromium.org>
Reviewed-by: Sara Kato <sarakato@chromium.org>
Reviewed-by: David Tseng <dtseng@chromium.org>
Cr-Commit-Position: refs/heads/master@{#704899}

chrome/browser/chromeos/arc/accessibility/arc_accessibility_helper_bridge.h

@@ -109,11 +109,11 @@ class ArcAccessibilityHelperBridge
 
   void set_filter_type_all_for_test() { use_filter_type_all_for_test_ = true; }
 
- protected:
+ private:
+  // virtual for testing.
   virtual aura::Window* GetActiveWindow();
   virtual extensions::EventRouter* GetEventRouter() const;
 
- private:
   std::unique_ptr<PrefChangeRegistrar> pref_change_registrar_;
   void UpdateCaptionSettings() const;
 

chrome/browser/chromeos/arc/accessibility/arc_accessibility_helper_bridge_unittest.cc

@@ -73,13 +73,12 @@ class ArcAccessibilityHelperBridgeTest : public ChromeViewsTestBase {
       return event_router_->GetEventCount(event_name);
     }
 
-   protected:
+   private:
     aura::Window* GetActiveWindow() override { return window_.get(); }
     extensions::EventRouter* GetEventRouter() const override {
       return event_router_;
     }
 
-   private:
     std::unique_ptr<aura::Window> window_;
     extensions::TestEventRouter* const event_router_;
 

chrome/browser/chromeos/arc/accessibility/ax_tree_source_arc.cc

@@ -262,7 +262,7 @@ void AXTreeSourceArc::GetChildren(
   // descendants.
   std::sort(
       out_children->begin(), out_children->end(),
-      [this, id_to_index](auto left, auto right) {
+      [this, &id_to_index](auto left, auto right) {
         auto left_bounds = ComputeEnclosingBounds(left);
         auto right_bounds = ComputeEnclosingBounds(right);
 

chrome/browser/chromeos/arc/accessibility/ax_tree_source_arc.h

@@ -89,11 +89,11 @@ class AXTreeSourceArc : public ui::AXTreeSource<ArcAccessibilityInfoData*,
 
   bool is_input_method_window() { return is_input_method_window_; }
 
- protected:
+ private:
+  // virtual for testing.
   virtual extensions::AutomationEventRouterInterface* GetAutomationEventRouter()
       const;
 
- private:
   friend class arc::AXTreeSourceArcTest;
   class FocusStealer;
 

chrome/browser/chromeos/arc/accessibility/ax_tree_source_arc_unittest.cc

@@ -137,12 +137,12 @@ class AXTreeSourceArcTest : public testing::Test,
                         MockAutomationEventRouter* router)
         : AXTreeSourceArc(delegate), router_(router) {}
 
+   private:
     extensions::AutomationEventRouterInterface* GetAutomationEventRouter()
         const override {
       return router_;
     }
 
-   private:
     MockAutomationEventRouter* const router_;
   };