Track text selection on the browser side (Mac)

content/browser/renderer_host/render_widget_host_view_aura.cc

Index: content/browser/renderer_host/render_widget_host_view_aura.cc
diff --git a/content/browser/renderer_host/render_widget_host_view_aura.cc b/content/browser/renderer_host/render_widget_host_view_aura.cc
index 0c313ec4e7b2ad07b267cb3627fcfdb3e04f9421..40a618aa66d6a7cdfa1a322923702dd1f037f458 100644
--- a/content/browser/renderer_host/render_widget_host_view_aura.cc
+++ b/content/browser/renderer_host/render_widget_host_view_aura.cc
@@ -3050,41 +3050,30 @@ void RenderWidgetHostViewAura::OnTextSelectionChanged(
   if (!GetTextInputManager())
     return;
 
-  const TextInputManager::TextSelection* text_selection = nullptr;
+  RenderWidgetHostViewBase* focused_view = nullptr;
   if (is_guest_view_hack_) {
     // We obtain the TextSelection from focused RWH which is obtained from the
     // frame tree. BrowserPlugin-based guests' RWH is not part of the frame tree
     // and the focused RWH will be that of the embedder which is incorrect. In
     // this case we should use TextSelection for |this| since RWHV for guest
     // forwards text selection information to its platform view.
-    text_selection = GetTextInputManager()->GetTextSelection(this);
+    focused_view = this;
   } else {
     RenderWidgetHostImpl* focused_widget =
         host_->delegate()->GetFocusedRenderWidgetHost(host_);
-    if (!!focused_widget && !!focused_widget->GetView()) {
-      text_selection = GetTextInputManager()->GetTextSelection(
-          focused_widget->GetView());
-    }
+    if (focused_widget)
+      focused_view = focused_widget->GetView();
   }
 
-  if (!text_selection)
-    return;
-
-  if (text_selection->text.empty() || text_selection->range.is_empty())
+  if (!focused_view)
     return;
-  size_t pos = text_selection->range.GetMin() - text_selection->offset;
-  size_t n = text_selection->range.length();
 
-  DCHECK(pos + n <= text_selection->text.length())
-      << "The text can not fully cover range.";
-  if (pos >= text_selection->text.length()) {
-    NOTREACHED() << "The text can not cover range.";
-    return;
+  base::string16 selected_text;
+  if (GetTextInputManager()->GetSelectedText(focused_view, &selected_text)) {
+    // Set the CLIPBOARD_TYPE_SELECTION to the ui::Clipboard.
+    ui::ScopedClipboardWriter clipboard_writer(ui::CLIPBOARD_TYPE_SELECTION);
+    clipboard_writer.WriteText(selected_text);
   }
-
-  // Set the CLIPBOARD_TYPE_SELECTION to the ui::Clipboard.
-  ui::ScopedClipboardWriter clipboard_writer(ui::CLIPBOARD_TYPE_SELECTION);
-  clipboard_writer.WriteText(text_selection->text.substr(pos, n));
 #endif  // defined(USE_X11) && !defined(OS_CHROMEOS)
 }