Reland: Implement Aura side of unified touch text selection for contents

content/browser/renderer_host/input/touch_selection_controller.h

Index: content/browser/renderer_host/input/touch_selection_controller.h
diff --git a/content/browser/renderer_host/input/touch_selection_controller.h b/content/browser/renderer_host/input/touch_selection_controller.h
index abe4ed46facc761a046c708cf0adaf51825a39f9..8ef3f3333ed1af68fd279039125078d825752dae 100644
--- a/content/browser/renderer_host/input/touch_selection_controller.h
+++ b/content/browser/renderer_host/input/touch_selection_controller.h
@@ -83,6 +83,12 @@ class CONTENT_EXPORT TouchSelectionController : public TouchHandleClient {
   // Returns true if an animation is active and requires further ticking.
   bool Animate(base::TimeTicks animate_time);
 
+  void ActivateSelection(const cc::ViewportSelectionBound& start,
+                         const cc::ViewportSelectionBound& end);
+
+  bool is_insertion_active() const { return is_insertion_active_; }
+  bool is_selection_active() const { return is_selection_active_; }
+
  private:
   enum InputEventType { TAP, LONG_PRESS, INPUT_EVENT_TYPE_NONE };