Supports the invisible underline for native input fields.

ui/views/controls/textfield/textfield.cc

Index: ui/views/controls/textfield/textfield.cc
diff --git a/ui/views/controls/textfield/textfield.cc b/ui/views/controls/textfield/textfield.cc
index 6ca37f960c9cba3cbe5bbbeb6e7bc75e4b21bf71..6320d37938f4da7c0238ff67603e842e62bffc49 100644
--- a/ui/views/controls/textfield/textfield.cc
+++ b/ui/views/controls/textfield/textfield.cc
@@ -1490,13 +1490,14 @@ bool Textfield::GetCompositionCharacterBounds(uint32 index,
   DCHECK(rect);
   if (!HasCompositionText())
     return false;
-  gfx::RenderText* render_text = GetRenderText();
-  const gfx::Range& composition_range = render_text->GetCompositionRange();
+  gfx::Range composition_range;
+  model_->GetCompositionTextRange(&composition_range);
   DCHECK(!composition_range.is_empty());
 
   size_t text_index = composition_range.start() + index;
   if (composition_range.end() <= text_index)
     return false;
+  gfx::RenderText* render_text = GetRenderText();
   if (!render_text->IsValidCursorIndex(text_index)) {
     text_index = render_text->IndexOfAdjacentGrapheme(
         text_index, gfx::CURSOR_BACKWARD);