[Contextual Search] Add support for tap on the selection.

ui/touch_selection/touch_selection_controller.cc

Index: ui/touch_selection/touch_selection_controller.cc
diff --git a/ui/touch_selection/touch_selection_controller.cc b/ui/touch_selection/touch_selection_controller.cc
index 3d52b4c3e423f276b65541c1491b0e260411fb86..9cdf1b8e593fd540c6745c3a8987246c2a9bba98 100644
--- a/ui/touch_selection/touch_selection_controller.cc
+++ b/ui/touch_selection/touch_selection_controller.cc
@@ -151,11 +151,26 @@ bool TouchSelectionController::WillHandleTouchEvent(const MotionEvent& event) {
   return false;
 }
 
-void TouchSelectionController::OnLongPressEvent() {
+bool TouchSelectionController::WillHandleLongPressEvent(
+    const gfx::PointF& location) {
+  // If there is an active selection that was not triggered by a user gesture,
+  // allow showing the handles for that selection if a long-press occurs within
+  // the selection rect. Note that this hit test is at best a crude
+  // approximation, and may swallow taps that actually fall outside the
+  // real selection.
+  if (!is_selection_active_ && !is_insertion_active_) {
+    if (GetStartPosition() != GetEndPosition() &&
+        RectFBetweenSelectionBounds(start_, end_).Contains(location)) {
+      AllowShowingFromCurrentSelection();
+      return true;
+    }
+  }
+
   response_pending_input_event_ = LONG_PRESS;
   ShowSelectionHandlesAutomatically();
   ShowInsertionHandleAutomatically();
   ResetCachedValuesIfInactive();
+  return false;
 }
 
 void TouchSelectionController::AllowShowingFromCurrentSelection() {
@@ -171,12 +186,24 @@ void TouchSelectionController::AllowShowingFromCurrentSelection() {
     OnInsertionChanged();
 }
 
-void TouchSelectionController::OnTapEvent() {
+bool TouchSelectionController::WillHandleTapEvent(const gfx::PointF& location) {
+  // If there is an active selection that was not triggered by a user gesture,
+  // allow showing the handles for that selection if the tap occurs within the
+  // selection rect. Note that this hit test is at best a crude approximation,
+  // and may swallow taps that actually fall outside the real selection.
+  if (!is_selection_active_ && !is_insertion_active_) {

[jdduke (slow), 2015/05/01 20:52:06]

Can we split this logic out into a shared function?

if (WillHandleTapOrLongPress(location))
  return true;

[Donn Denman, 2015/05/01 22:46:03]

Done.

+    if (GetStartPosition() != GetEndPosition() &&
+        RectFBetweenSelectionBounds(start_, end_).Contains(location)) {
+      AllowShowingFromCurrentSelection();
+      return true;
+    }
+  }
   response_pending_input_event_ = TAP;
   ShowInsertionHandleAutomatically();
   if (selection_empty_ && !show_on_tap_for_empty_editable_)
     DeactivateInsertion();
   ResetCachedValuesIfInactive();
+  return false;
 }
 
 void TouchSelectionController::HideAndDisallowShowingAutomatically() {