[Android] Introduce state machine in stylus text selection

content/browser/renderer_host/input/stylus_text_selector.h

Index: content/browser/renderer_host/input/stylus_text_selector.h
diff --git a/content/browser/renderer_host/input/stylus_text_selector.h b/content/browser/renderer_host/input/stylus_text_selector.h
index 05d2f1803822ae3f4dbe27fea06ab87b211e5977..1c1a9d1e0a05c424b314bac6682d8c0edad15615 100644
--- a/content/browser/renderer_host/input/stylus_text_selector.h
+++ b/content/browser/renderer_host/input/stylus_text_selector.h
@@ -50,6 +50,11 @@ class CONTENT_EXPORT StylusTextSelector : public ui::SimpleGestureListener {
   bool OnTouchEvent(const ui::MotionEvent& event);
 
  private:
+  enum DragState {
+    NO_DRAG,
+    DRAGGING_WITH_BUTTON_PRESSED,
+    DRAGGING_WITH_BUTTON_RELEASED,
+  };
   friend class StylusTextSelectorTest;
   FRIEND_TEST_ALL_PREFIXES(StylusTextSelectorTest, ShouldStartTextSelection);
 
@@ -66,8 +71,7 @@ class CONTENT_EXPORT StylusTextSelector : public ui::SimpleGestureListener {
   StylusTextSelectorClient* client_;
   bool text_selection_triggered_;
   bool secondary_button_pressed_;
-  bool dragging_;
-  bool dragged_;
+  DragState drag_state_;
   float anchor_x_;
   float anchor_y_;
   std::unique_ptr<ui::GestureDetector> gesture_detector_;