Make AXPlatformNodeDelegate::GetData() const

ui/accessibility/platform/test_ax_node_wrapper.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_ACCESSIBILITY_PLATFORM_TEST_AX_NODE_WRAPPER_H_
 #define UI_ACCESSIBILITY_PLATFORM_TEST_AX_NODE_WRAPPER_H_
 
 #include "ui/accessibility/ax_node.h"
 #include "ui/accessibility/ax_tree.h"
 #include "ui/accessibility/platform/ax_platform_node.h"
@@ skipping 11 matching lines @@
   static TestAXNodeWrapper* GetOrCreate(AXTree* tree, AXNode* node);
 
   // Set a global coordinate offset for testing.
   static void SetGlobalCoordinateOffset(const gfx::Vector2d& offset);
 
   virtual ~TestAXNodeWrapper();
 
   AXPlatformNode* ax_platform_node() { return platform_node_; }
 
   // AXPlatformNodeDelegate.
-  const AXNodeData& GetData() override;
+  const AXNodeData& GetData() const override;
   gfx::NativeWindow GetTopLevelWidget() override;
   gfx::NativeViewAccessible GetParent() override;
   int GetChildCount() override;
   gfx::NativeViewAccessible ChildAtIndex(int index) override;
   gfx::Vector2d GetGlobalCoordinateOffset() override;
   gfx::NativeViewAccessible HitTestSync(int x, int y) override;
   gfx::NativeViewAccessible GetFocus() override;
   gfx::AcceleratedWidget GetTargetForNativeAccessibilityEvent() override;
   bool AccessibilityPerformAction(const ui::AXActionData& data) override;
   void DoDefaultAction() override;
 
  private:
   TestAXNodeWrapper(AXTree* tree, AXNode* node);
 
   AXTree* tree_;
   AXNode* node_;
   AXPlatformNode* platform_node_;
 };
 
 }  // namespace ui
 
 #endif  // UI_ACCESSIBILITY_PLATFORM_TEST_AX_NODE_WRAPPER_H_