wip: Touch Text Selection Prototypes

ui/touch_selection/selection_granularity.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_TOUCH_SELECTION_SELECTION_GRANULARITY_
 #define UI_TOUCH_SELECTION_SELECTION_GRANULARITY_
 
 namespace ui {
 
 enum TextSelectionGranularity {
   CHARACTER_GRANULARITY,
   WORD_GRANULARITY,
   SENTENCE_GRANULARITY,
   LINE_GRANULARITY,
   PARAGRAPH_GRANULARITY
 };
 
+enum TextSelectionGranularityStrategy {
+  // Always using CHARACTER_GRANULARITY
+  GRANULARITY_STRATEGY_DEFAULT,
+  // Switches between WORD_GRANULARITY and CHARACTER_GRANULARITY
+  // Depending on whether the selection or growing or shrinking
+  GRANULARITY_STRATEGY_DIRECTION,
+  // Switches between WORD_GRANULARITY and CHARACTER_GRANULARITY
+  // Depending on the handle move velocity.
+  GRANULARITY_STRATEGY_VELOCITY
+};
+
 }  // namespace ui
 
 #endif  // UI_TOUCH_SELECTION_SELECTION_GRANULARITY_