Implement AXPlatformNodeWin::get_indexInParent

BUG=462748

Review URL: https://codereview.chromium.org/1019663002

Cr-Commit-Position: refs/heads/master@{#321242}

ui/accessibility/platform/ax_platform_node_win.cc

@@ -572,6 +572,15 @@ STDMETHODIMP AXPlatformNodeWin::get_attributes(BSTR* attributes) {
   return S_OK;
 }
 
+STDMETHODIMP AXPlatformNodeWin::get_indexInParent(LONG* index_in_parent) {
+  COM_OBJECT_VALIDATE_1_ARG(index_in_parent);
+  *index_in_parent = GetIndexInParent();
+  if (*index_in_parent < 0)
+    return E_FAIL;
+
+  return S_OK;
+}
+
 //
 // IAccessibleText
 //

ui/accessibility/platform/ax_platform_node_win.h

@@ -129,6 +129,8 @@ AXPlatformNodeWin
 
   STDMETHODIMP get_attributes(BSTR* attributes) override;
 
+  STDMETHODIMP get_indexInParent(LONG* index_in_parent) override;
+
   //
   // IAccessible2 methods not implemented.
   //
@@ -136,9 +138,6 @@ AXPlatformNodeWin
   STDMETHODIMP get_attribute(BSTR name, VARIANT* attribute) override {
     return E_NOTIMPL;
   }
-  STDMETHODIMP get_indexInParent(LONG* index_in_parent) override {
-    return E_NOTIMPL;
-  }
   STDMETHODIMP get_extendedRole(BSTR* extended_role) override {
     return E_NOTIMPL;
   }

ui/accessibility/platform/ax_platform_node_win_unittest.cc

@@ -369,4 +369,40 @@ TEST_F(AXPlatformNodeWinTest, TestIAccessibleChildAndParent) {
   }
 }
 
+TEST_F(AXPlatformNodeWinTest, TestIAccessible2IndexInParent) {
+  AXNodeData root;
+  root.id = 1;
+  root.role = AX_ROLE_ROOT_WEB_AREA;
+  root.child_ids.push_back(2);
+  root.child_ids.push_back(3);
+
+  AXNodeData left;
+  left.id = 2;
+
+  AXNodeData right;
+  right.id = 3;
+
+  Init(root, left, right);
+  ScopedComPtr<IAccessible> root_iaccessible(GetRootIAccessible());
+  ScopedComPtr<IAccessible2> root_iaccessible2 =
+      ToIAccessible2(root_iaccessible);
+  ScopedComPtr<IAccessible> left_iaccessible(
+      IAccessibleFromNode(GetRootNode()->children()[0]));
+  ScopedComPtr<IAccessible2> left_iaccessible2 =
+      ToIAccessible2(left_iaccessible);
+  ScopedComPtr<IAccessible> right_iaccessible(
+      IAccessibleFromNode(GetRootNode()->children()[1]));
+  ScopedComPtr<IAccessible2> right_iaccessible2 =
+      ToIAccessible2(right_iaccessible);
+
+  LONG index;
+  ASSERT_EQ(E_FAIL, root_iaccessible2->get_indexInParent(&index));
+
+  ASSERT_EQ(S_OK, left_iaccessible2->get_indexInParent(&index));
+  EXPECT_EQ(0, index);
+
+  ASSERT_EQ(S_OK, right_iaccessible2->get_indexInParent(&index));
+  EXPECT_EQ(1, index);
+}
+
 }  // namespace ui