Stand Up IsOffscreen in AXPlatformNodeWin::GetPropertyValue

- Enabled/implemented IsOffscreen property for UIA in
AXPlatformNodeWin::GetPropertyValue and assoicated browser tests.
GetPropertyValue calculates isOffscreen status by utilizing
AXTree::RelativeToTreeBounds, which looks at the bounds of the
node relative to its ancestor and rootWebArea bounds to determine
the isOffscreen status.

- Modified AccessibilityWinBrowserTests::FindNodeInSubtree to take
into account of StringAttribute::kValue when finding the node.

Bug: 844149
Change-Id: Ied62e00814957a6ca97b1849935ec692f1acf03a
Reviewed-on: https://chromium-review.googlesource.com/c/1481800
Commit-Queue: Victor Fei <vicfei@microsoft.com>
Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#636934}

content/browser/accessibility/accessibility_win_browsertest.cc

@@ -98,7 +98,8 @@ class AccessibilityWinBrowserTest : public ContentBrowserTest {
   void SetUpSampleParagraphInScrollableEditable(
       Microsoft::WRL::ComPtr<IAccessibleText>* accessible_text,
       ui::AXMode accessibility_mode = ui::kAXModeComplete);
-  BrowserAccessibility* FindNode(ax::mojom::Role role, const std::string& name);
+  BrowserAccessibility* FindNode(ax::mojom::Role role,
+                                 const std::string& name_or_value);
   BrowserAccessibilityManager* GetManager();
   static Microsoft::WRL::ComPtr<IAccessible> GetAccessibleFromVariant(
       IAccessible* parent,
@@ -126,7 +127,7 @@ class AccessibilityWinBrowserTest : public ContentBrowserTest {
       Microsoft::WRL::ComPtr<IAccessibleText>* accessible_text);
   BrowserAccessibility* FindNodeInSubtree(BrowserAccessibility& node,
                                           ax::mojom::Role role,
-                                          const std::string& name);
+                                          const std::string& name_or_value);
   DISALLOW_COPY_AND_ASSIGN(AccessibilityWinBrowserTest);
 };
 
@@ -477,30 +478,41 @@ void AccessibilityWinBrowserTest::SetUpSampleParagraphHelper(
   ASSERT_HRESULT_SUCCEEDED(paragraph.CopyTo(accessible_text->GetAddressOf()));
 }
 
+// Retrieve the accessibility node, starting from the root node, that matches
+// the accessibility role, name or value.
 BrowserAccessibility* AccessibilityWinBrowserTest::FindNode(
     ax::mojom::Role role,
-    const std::string& name) {
+    const std::string& name_or_value) {
   BrowserAccessibility* root = GetManager()->GetRoot();
   CHECK(root);
-  return FindNodeInSubtree(*root, role, name);
+  return FindNodeInSubtree(*root, role, name_or_value);
 }
 
+// Retrieve the browser accessibility manager object for the current web
+// contents.
 BrowserAccessibilityManager* AccessibilityWinBrowserTest::GetManager() {
   WebContentsImpl* web_contents =
       static_cast<WebContentsImpl*>(shell()->web_contents());
   return web_contents->GetRootBrowserAccessibilityManager();
 }
 
+// Retrieve the accessibility node in the subtree that matches the accessibility
+// role, name or value.
 BrowserAccessibility* AccessibilityWinBrowserTest::FindNodeInSubtree(
     BrowserAccessibility& node,
     ax::mojom::Role role,
-    const std::string& name) {
+    const std::string& name_or_value) {
+  const auto& name = node.GetStringAttribute(ax::mojom::StringAttribute::kName);
+  const auto& value =
+      node.GetStringAttribute(ax::mojom::StringAttribute::kValue);
   if (node.GetRole() == role &&
-      node.GetStringAttribute(ax::mojom::StringAttribute::kName) == name)
+      (name == name_or_value || value == name_or_value)) {
     return &node;
+  }
+
   for (unsigned int i = 0; i < node.PlatformChildCount(); ++i) {
     BrowserAccessibility* result =
-        FindNodeInSubtree(*node.PlatformGetChild(i), role, name);
+        FindNodeInSubtree(*node.PlatformGetChild(i), role, name_or_value);
     if (result)
       return result;
   }

content/browser/accessibility/dump_accessibility_tree_browsertest.cc

@@ -1750,11 +1750,21 @@ IN_PROC_BROWSER_TEST_F(DumpAccessibilityTreeTest, AccessibilityOffscreen) {
   RunHtmlTest(FILE_PATH_LITERAL("offscreen.html"));
 }
 
+IN_PROC_BROWSER_TEST_F(DumpAccessibilityTreeTest,
+                       AccessibilityOffscreenIframe) {
+  RunHtmlTest(FILE_PATH_LITERAL("offscreen-iframe.html"));
+}
+
 IN_PROC_BROWSER_TEST_F(DumpAccessibilityTreeTest,
                        AccessibilityOffscreenScroll) {
   RunHtmlTest(FILE_PATH_LITERAL("offscreen-scroll.html"));
 }
 
+IN_PROC_BROWSER_TEST_F(DumpAccessibilityTreeTest,
+                       AccessibilityOffscreenSelect) {
+  RunHtmlTest(FILE_PATH_LITERAL("offscreen-select.html"));
+}
+
 IN_PROC_BROWSER_TEST_F(DumpAccessibilityTreeTest, AccessibilityOptgroup) {
   RunHtmlTest(FILE_PATH_LITERAL("optgroup.html"));
 }

content/test/data/accessibility/html/offscreen-iframe-content.html

+<!doctype html>
+<html>
+<body>
+  <div aria-label="iframe_onscreen" style="height:300px; background-color: red;"></div>
+  <div aria-label="iframe_offscreen" style="height:200px; background-color: green"></div>
+</body>
+</html>

content/test/data/accessibility/html/offscreen-iframe-expected-blink.txt

+rootWebArea
+++genericContainer
+++++iframe
+++++++rootWebArea
+++++++++genericContainer name='iframe_onscreen'
+++++++++genericContainer offscreen name='iframe_offscreen'

content/test/data/accessibility/html/offscreen-iframe-expected-win.txt

+ROLE_SYSTEM_DOCUMENT READONLY FOCUSABLE
+++IA2_ROLE_SECTION
+++++IA2_ROLE_INTERNAL_FRAME
+++++++ROLE_SYSTEM_DOCUMENT READONLY FOCUSABLE
+++++++++IA2_ROLE_SECTION name='iframe_onscreen'
+++++++++IA2_ROLE_SECTION name='iframe_offscreen' OFFSCREEN

content/test/data/accessibility/html/offscreen-iframe.html

+<!--
+@WIN-ALLOW:OFFSCREEN
+@BLINK-ALLOW:offscreen
+-->
+
+<html>
+<body>
+  <iframe height="300px" width="200px" src="offscreen-iframe-content.html"></iframe>
+</body>
+</html>

content/test/data/accessibility/html/offscreen-select-expected-blink.txt

+rootWebArea
+++popUpButton collapsed value='Onscreen 1'
+++++menuListPopup invisible
+++++++menuListOption name='Onscreen 1' selected=true
+++++++menuListOption invisible name='Onscreen 2' selected=false
+++++++menuListOption invisible name='Onscreen 3' selected=false
+++popUpButton collapsed offscreen value='Offscreen 1'
+++++menuListPopup invisible
+++++++menuListOption offscreen name='Offscreen 1' selected=true
+++++++menuListOption invisible offscreen name='Offscreen 2' selected=false
+++++++menuListOption invisible offscreen name='Offscreen 3' selected=false

content/test/data/accessibility/html/offscreen-select-expected-win.txt

+ROLE_SYSTEM_DOCUMENT READONLY FOCUSABLE
+++ROLE_SYSTEM_COMBOBOX value='Onscreen 1' COLLAPSED FOCUSABLE HASPOPUP
+++++ROLE_SYSTEM_LIST INVISIBLE
+++++++ROLE_SYSTEM_LISTITEM name='Onscreen 1' SELECTED FOCUSABLE
+++++++ROLE_SYSTEM_LISTITEM name='Onscreen 2' INVISIBLE FOCUSABLE
+++++++ROLE_SYSTEM_LISTITEM name='Onscreen 3' INVISIBLE FOCUSABLE
+++ROLE_SYSTEM_COMBOBOX value='Offscreen 1' COLLAPSED OFFSCREEN FOCUSABLE HASPOPUP
+++++ROLE_SYSTEM_LIST INVISIBLE
+++++++ROLE_SYSTEM_LISTITEM name='Offscreen 1' SELECTED OFFSCREEN FOCUSABLE
+++++++ROLE_SYSTEM_LISTITEM name='Offscreen 2' INVISIBLE OFFSCREEN FOCUSABLE
+++++++ROLE_SYSTEM_LISTITEM name='Offscreen 3' INVISIBLE OFFSCREEN FOCUSABLE

content/test/data/accessibility/html/offscreen-select.html

+<!--
+@WIN-ALLOW:OFFSCREEN
+@BLINK-ALLOW:offscreen
+-->
+
+<html>
+<body>
+  <!-- Test when list box items are onscreen
+    Currently collapsed <option> elements are treated as onscreen, but this
+    probably isn't the most correct behavior, we should fix it.
+    http://crbug.com/937386 -->
+  <select name="Select onscreen">
+    <option value="1">Onscreen 1</option>
+    <option value="2">Onscreen 2</option>
+    <option value="3">Onscreen 3</option>
+  </select>
+
+  <div style="height:650px"></div>
+
+  <!-- Test when list box items are offscreen -->
+  <select name="Select offscreen">
+    <option value="1">Offscreen 1</option>
+    <option value="2">Offscreen 2</option>
+    <option value="3">Offscreen 3</option>
+  </select>
+</body>
+</html>

ui/accessibility/platform/ax_platform_node_win.cc

@@ -3695,6 +3695,12 @@ IFACEMETHODIMP AXPlatformNodeWin::GetPropertyValue(PROPERTYID property_id,
                             : VARIANT_FALSE;
       break;
 
+    case UIA_IsOffscreenPropertyId:
+      result->vt = VT_BOOL;
+      result->boolVal =
+          GetDelegate()->IsOffscreen() ? VARIANT_TRUE : VARIANT_FALSE;
+      break;
+
     case UIA_IsRequiredForFormPropertyId:
       result->vt = VT_BOOL;
       if (data.HasState(ax::mojom::State::kRequired)) {
@@ -3847,7 +3853,6 @@ IFACEMETHODIMP AXPlatformNodeWin::GetPropertyValue(PROPERTYID property_id,
     // Covered by MSAA.
     case UIA_BoundingRectanglePropertyId:
     case UIA_HelpTextPropertyId:
-    case UIA_IsOffscreenPropertyId:
     case UIA_NativeWindowHandlePropertyId:
     case UIA_ProcessIdPropertyId:
       break;

ui/accessibility/platform/ax_platform_node_win_unittest.cc

@@ -3219,6 +3219,7 @@ TEST_F(AXPlatformNodeWinTest, TestUIAGetPropertySimple) {
   EXPECT_UIA_BOOL_EQ(root_node, UIA_IsRequiredForFormPropertyId, false);
   EXPECT_UIA_BOOL_EQ(root_node, UIA_IsDataValidForFormPropertyId, true);
   EXPECT_UIA_BOOL_EQ(root_node, UIA_IsKeyboardFocusablePropertyId, false);
+  EXPECT_UIA_BOOL_EQ(root_node, UIA_IsOffscreenPropertyId, false);
   ComPtr<IRawElementProviderSimple> child_node1 =
       QueryInterfaceFromNode<IRawElementProviderSimple>(
           GetRootNode()->children()[0]);