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 1ded1a97a1c7e607200cf918782cd968b9cbf3f7..38d6e8727b956a4ac90bee9f3dbae2a033027fc6 100644
--- a/content/browser/renderer_host/input/touch_selection_controller.h
+++ b/content/browser/renderer_host/input/touch_selection_controller.h
@@ -82,6 +82,12 @@ 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 };