Revert of Fixes for contenteditable caret and selection handling in Windows.

content/browser/accessibility/browser_accessibility_win.cc

Index: content/browser/accessibility/browser_accessibility_win.cc
diff --git a/content/browser/accessibility/browser_accessibility_win.cc b/content/browser/accessibility/browser_accessibility_win.cc
index 7f77ad28ac986eb41b4a5fc0886265c3121ad474..74e7f11e9007eb663a1439485e688d45cbe89219 100644
--- a/content/browser/accessibility/browser_accessibility_win.cc
+++ b/content/browser/accessibility/browser_accessibility_win.cc
@@ -205,11 +205,6 @@
   HRESULT hr = CComObject<BrowserAccessibilityWin>::CreateInstance(&instance);
   DCHECK(SUCCEEDED(hr));
   return instance->NewReference();
-}
-
-const BrowserAccessibilityWin* BrowserAccessibility::ToBrowserAccessibilityWin()
-    const {
-  return static_cast<const BrowserAccessibilityWin*>(this);
 }
 
 BrowserAccessibilityWin* BrowserAccessibility::ToBrowserAccessibilityWin() {
@@ -2015,9 +2010,8 @@
 
   int selection_start, selection_end;
   GetSelectionOffsets(&selection_start, &selection_end);
-  // The caret is always at the end of the selection, if a selection exists.
-  *offset = selection_end;
-  if (*offset < 0)
+  *offset = selection_start;
+  if (selection_start < 0)
     return S_FALSE;
 
   return S_OK;
@@ -2071,9 +2065,8 @@
   int selection_start, selection_end;
   GetSelectionOffsets(&selection_start, &selection_end);
   if (selection_start >= 0 && selection_end >= 0 &&
-      selection_start != selection_end) {
+      selection_start != selection_end)
     *n_selections = 1;
-  }
 
   return S_OK;
 }
@@ -2096,13 +2089,6 @@
   int selection_start, selection_end;
   GetSelectionOffsets(&selection_start, &selection_end);
   if (selection_start >= 0 && selection_end >= 0) {
-    // We should ignore the direction of the selection when exposing start and
-    // end offsets. According to the IA2 Spec the end offset is always increased
-    // by one past the end of the selection. This wouldn't make sense if
-    // end < start.
-    if (selection_end < selection_start)
-      std::swap(selection_start, selection_end);
-
     *start_offset = selection_start;
     *end_offset = selection_end;
   }
@@ -3662,9 +3648,6 @@
 
 int32 BrowserAccessibilityWin::GetHyperlinkIndexFromChild(
     const BrowserAccessibilityWin& child) const {
-  if (hyperlinks().empty())
-    return -1;
-
   auto iterator = std::find(
       hyperlinks().begin(), hyperlinks().end(), child.GetId());
   if (iterator == hyperlinks().end())
@@ -3675,7 +3658,8 @@
 
 int32 BrowserAccessibilityWin::GetHypertextOffsetFromHyperlinkIndex(
     int32 hyperlink_index) const {
-  for (auto& offset_index : hyperlink_offset_to_index()) {
+  auto& offsets_map = hyperlink_offset_to_index();
+  for (auto& offset_index : offsets_map) {
     if (offset_index.second == hyperlink_index)
       return offset_index.first;
   }
@@ -3706,84 +3690,6 @@
   return parent_object->GetHypertextOffsetFromChild(*current_object);
 }
 
-int BrowserAccessibilityWin::GetHypertextOffsetFromEndpoint(
-    const BrowserAccessibilityWin& endpoint_object,
-    int endpoint_offset) const {
-  // There are three cases:
-  // 1. Either the selection endpoint is inside this object or is an ancestor of
-  // of this object. endpoint_offset should be returned.
-  // 2. The selection endpoint is a pure descendant of this object. The offset
-  // of the embedded object character corresponding to the subtree in which
-  // the endpoint is located should be returned.
-  // 3. The selection endpoint is in a completely different part of the tree.
-  // Either 0 or text_length should be returned depending on the direction that
-  // one needs to travel to find the endpoint.
-
-  // Case 1.
-  //
-  // IsDescendantOf includes the case when endpoint_object == this.
-  if (IsDescendantOf(&endpoint_object) ||
-      // Handle the case when the endpoint is a direct text-only child.
-      // The selection offset should still be valid on the parent.
-      (endpoint_object.IsTextOnlyObject() &&
-       endpoint_object.GetParent() == this)) {
-    return endpoint_offset;
-  }
-
-  const BrowserAccessibility* common_parent = this;
-  while (common_parent && !endpoint_object.IsDescendantOf(common_parent)) {
-    common_parent = common_parent->GetParent();
-  }
-  if (!common_parent)
-    return -1;
-
-  auto common_parent_win = common_parent->ToBrowserAccessibilityWin();
-  // Text only objects must have a parent.
-  DCHECK(!IsTextOnlyObject() || GetParent());
-  DCHECK(!endpoint_object.IsTextOnlyObject() || endpoint_object.GetParent());
-  // Text only objects that are direct descendants should behave as if they
-  // are part of their parent when computing hyperlink offsets.
-  const BrowserAccessibilityWin* nearest_non_text_ancestor =
-      IsTextOnlyObject() ? GetParent()->ToBrowserAccessibilityWin() : this;
-  const BrowserAccessibilityWin& nearest_non_text_endpoint =
-      endpoint_object.IsTextOnlyObject()
-          ? *(endpoint_object.GetParent()->ToBrowserAccessibilityWin())
-          : endpoint_object;
-
-  // Case 2.
-  //
-  // We already checked in case 1 if our endpoint is inside this object.
-  // We can safely assume that it is a descendant or in a completely different
-  // part of the tree.
-  if (common_parent_win == nearest_non_text_ancestor) {
-    return nearest_non_text_ancestor->GetHypertextOffsetFromDescendant(
-        nearest_non_text_endpoint);
-  }
-
-  // Case 3.
-  //
-  // We can safely assume that the endpoint is in another part of the tree or
-  // at common parent, and that this object is a descendant of common parent.
-  int current_offset =
-      static_cast<int>(common_parent_win->GetHypertextOffsetFromDescendant(
-          *nearest_non_text_ancestor));
-  DCHECK_GE(current_offset, 0);
-  if (common_parent_win != &nearest_non_text_endpoint) {
-    endpoint_offset =
-        static_cast<int>(common_parent_win->GetHypertextOffsetFromDescendant(
-            nearest_non_text_endpoint));
-    DCHECK_GE(endpoint_offset, 0);
-  }
-
-  if (endpoint_offset < current_offset)
-    return 0;
-  if (endpoint_offset > current_offset)
-    return TextForIAccessibleText().length();
-
-  NOTREACHED();
-  return -1;
-}
-
 int BrowserAccessibilityWin::GetSelectionAnchor() const {
   BrowserAccessibility* root = manager()->GetRoot();
   int32 anchor_id;
@@ -3795,11 +3701,23 @@
   if (!anchor_object)
     return -1;
 
-  int anchor_offset;
-  if (!root->GetIntAttribute(ui::AX_ATTR_ANCHOR_OFFSET, &anchor_offset))
-    return -1;
-
-  return GetHypertextOffsetFromEndpoint(*anchor_object, anchor_offset);
+  // Includes the case when anchor_object == this.
+  if (IsDescendantOf(anchor_object) ||
+      // Text only objects that are direct descendants should behave as if they
+      // are part of this object when computing hypertext.
+      (anchor_object->GetParent() == this &&
+      anchor_object->IsTextOnlyObject())) {
+    int anchor_offset;
+    if (!root->GetIntAttribute(ui::AX_ATTR_ANCHOR_OFFSET, &anchor_offset))
+      return -1;
+
+    return anchor_offset;
+  }
+
+  if (anchor_object->IsDescendantOf(this))
+    return GetHypertextOffsetFromDescendant(*anchor_object);
+
+  return -1;
 }
 
 int BrowserAccessibilityWin::GetSelectionFocus() const {
@@ -3813,11 +3731,22 @@
   if (!focus_object)
     return -1;
 
-  int focus_offset;
-  if (!root->GetIntAttribute(ui::AX_ATTR_FOCUS_OFFSET, &focus_offset))
-    return -1;
-
-  return GetHypertextOffsetFromEndpoint(*focus_object, focus_offset);
+  // Includes the case when focus_object == this.
+  if (IsDescendantOf(focus_object) ||
+      // Text only objects that are direct descendants should behave as if they
+      // are part of this object when computing hypertext.
+      (focus_object->GetParent() == this && focus_object->IsTextOnlyObject())) {
+    int focus_offset;
+    if (!root->GetIntAttribute(ui::AX_ATTR_FOCUS_OFFSET, &focus_offset))
+      return -1;
+
+    return focus_offset;
+  }
+
+  if (focus_object->IsDescendantOf(this))
+    return GetHypertextOffsetFromDescendant(*focus_object);
+
+  return -1;
 }
 
 void BrowserAccessibilityWin::GetSelectionOffsets(
@@ -3835,56 +3764,15 @@
   if (*selection_start < 0 || *selection_end < 0)
     return;
 
-  // If the selection is collapsed or if it only spans one character, return the
-  // selection offsets only if the caret is active on this object or any of its
-  // children.
-  // The focus object indicates the caret position.
-  if (*selection_start == *selection_end) {
-    BrowserAccessibility* root = manager()->GetRoot();
-    int32 focus_id;
-    if (!root || !root->GetIntAttribute(ui::AX_ATTR_FOCUS_OBJECT_ID, &focus_id))
-      return;
-
-    BrowserAccessibilityWin* focus_object =
-        manager()->GetFromID(focus_id)->ToBrowserAccessibilityWin();
-    if (!focus_object)
-      return;
-
-    if (!focus_object->IsDescendantOf(this) &&
-        !(IsTextOnlyObject() && GetParent() == focus_object)) {
-      *selection_start = -1;
-      *selection_end = -1;
-      return;
-    }
-  }
-
-  // The IA2 Spec says that if the largest of the two offsets falls on an
-  // embedded object character and if there is a selection in that embedded
-  // object, it should be incremented by one so that it points after the
-  // embedded object character.
-  // This is a signal to AT software that the embedded object is also part of
-  // the selection.
-  int* largest_offset =
-      (*selection_start <= *selection_end) ? selection_end : selection_start;
-  auto current_object = const_cast<BrowserAccessibilityWin*>(this);
-  LONG hyperlink_index;
-  HRESULT hr =
-      current_object->get_hyperlinkIndex(*largest_offset, &hyperlink_index);
-  if (hr != S_OK)
-    return;
-
-  DCHECK_GE(hyperlink_index, 0);
-  base::win::ScopedComPtr<IAccessibleHyperlink> hyperlink;
-  hr = current_object->get_hyperlink(hyperlink_index, hyperlink.Receive());
-  DCHECK(SUCCEEDED(hr));
-  base::win::ScopedComPtr<IAccessibleText> hyperlink_text;
-  hr = hyperlink.QueryInterface(hyperlink_text.Receive());
-  DCHECK(SUCCEEDED(hr));
-  LONG n_selections = 0;
-  hr = hyperlink_text->get_nSelections(&n_selections);
-  DCHECK(SUCCEEDED(hr));
-  if (n_selections > 0)
-    ++(*largest_offset);
+  if (*selection_end < *selection_start)
+    std::swap(*selection_start, *selection_end);
+
+  // IA2 Spec says that the end of the selection should be after the last
+  // embedded object character that is part of the selection, if there is one.
+  if (hyperlink_offset_to_index().find(*selection_end) !=
+      hyperlink_offset_to_index().end()) {
+    ++(*selection_end);
+  }
 }
 
 base::string16 BrowserAccessibilityWin::GetNameRecursive() const {
@@ -3911,7 +3799,7 @@
   return value;
 }
 
-base::string16 BrowserAccessibilityWin::TextForIAccessibleText() const {
+base::string16 BrowserAccessibilityWin::TextForIAccessibleText() {
   switch (GetRole()) {
     case ui::AX_ROLE_TEXT_FIELD:
     case ui::AX_ROLE_MENU_LIST_OPTION: