Be explicit about forcing TouchSelectionController updates

ui/touch_selection/touch_selection_controller.cc

 // Copyright 2014 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.
 
 #include "ui/touch_selection/touch_selection_controller.h"
 
 #include "base/auto_reset.h"
 #include "base/logging.h"
 #include "base/metrics/histogram_macros.h"
 
@@ skipping 30 matching lines @@
 }  // namespace
 
 TouchSelectionController::TouchSelectionController(
     TouchSelectionControllerClient* client,
     base::TimeDelta tap_timeout,
     float tap_slop,
     bool show_on_tap_for_empty_editable)
     : client_(client),
       tap_timeout_(tap_timeout),
       tap_slop_(tap_slop),
+      force_next_update_(false),
       show_on_tap_for_empty_editable_(show_on_tap_for_empty_editable),
       response_pending_input_event_(INPUT_EVENT_TYPE_NONE),
       start_orientation_(TouchHandleOrientation::UNDEFINED),
       end_orientation_(TouchHandleOrientation::UNDEFINED),
       active_status_(INACTIVE),
       activate_insertion_automatically_(false),
       activate_selection_automatically_(false),
       selection_empty_(false),
       selection_editable_(false),
       temporarily_hidden_(false),
       selection_handle_dragged_(false) {
   DCHECK(client_);
 }
 
 TouchSelectionController::~TouchSelectionController() {
 }
 
 void TouchSelectionController::OnSelectionBoundsChanged(
     const SelectionBound& start,
     const SelectionBound& end) {
-  if (start == start_ && end_ == end)
+  if (!force_next_update_ && start == start_ && end_ == end)
     return;
 
   start_ = start;
   end_ = end;
   start_orientation_ = ToTouchHandleOrientation(start_.type());
   end_orientation_ = ToTouchHandleOrientation(end_.type());
+  force_next_update_ = false;
 
   if (!activate_selection_automatically_ &&
       !activate_insertion_automatically_) {
     DCHECK_EQ(INACTIVE, active_status_);
     DCHECK_EQ(INPUT_EVENT_TYPE_NONE, response_pending_input_event_);
     return;
   }
 
   // Ensure that |response_pending_input_event_| is cleared after the method
   // completes, while also making its current value available for the duration
@@ skipping 60 matching lines @@
     return end_selection_handle_->WillHandleTouchEvent(event);
   }
 
   return false;
 }
 
 void TouchSelectionController::OnLongPressEvent() {
   response_pending_input_event_ = LONG_PRESS;
   ShowSelectionHandlesAutomatically();
   ShowInsertionHandleAutomatically();
-  ResetCachedValuesIfInactive();
+  ForceNextUpdateIfInactive();
 }
 
 void TouchSelectionController::AllowShowingFromCurrentSelection() {
   if (active_status_ != INACTIVE)
     return;
 
   activate_selection_automatically_ = true;
   activate_insertion_automatically_ = true;
   if (GetStartPosition() != GetEndPosition()) {
     OnSelectionChanged();
   } else if (start_orientation_ == TouchHandleOrientation::CENTER &&
              selection_editable_) {
     OnInsertionChanged();
   }
 }
 
 void TouchSelectionController::OnTapEvent() {
   response_pending_input_event_ = TAP;
   if (active_status_ != SELECTION_ACTIVE)
     activate_selection_automatically_ = false;
   ShowInsertionHandleAutomatically();
   if (selection_empty_ && !show_on_tap_for_empty_editable_)
     DeactivateInsertion();
-  ResetCachedValuesIfInactive();
+  ForceNextUpdateIfInactive();
 }
 
 void TouchSelectionController::HideAndDisallowShowingAutomatically() {
   response_pending_input_event_ = INPUT_EVENT_TYPE_NONE;
   DeactivateInsertion();
   DeactivateSelection();
   activate_insertion_automatically_ = false;
   activate_selection_automatically_ = false;
 }
 
 void TouchSelectionController::SetTemporarilyHidden(bool hidden) {
   if (temporarily_hidden_ == hidden)
     return;
   temporarily_hidden_ = hidden;
 
   TouchHandle::AnimationStyle animation_style = GetAnimationStyle(true);
   if (active_status_ == SELECTION_ACTIVE) {
     start_selection_handle_->SetVisible(GetStartVisible(), animation_style);
     end_selection_handle_->SetVisible(GetEndVisible(), animation_style);
   } else if (active_status_ == INSERTION_ACTIVE) {
     insertion_handle_->SetVisible(GetStartVisible(), animation_style);
   }
 }
 
 void TouchSelectionController::OnSelectionEditable(bool editable) {
   if (selection_editable_ == editable)
     return;
   selection_editable_ = editable;
-  ResetCachedValuesIfInactive();
+  ForceNextUpdateIfInactive();
   if (!selection_editable_)
     DeactivateInsertion();
 }
 
 void TouchSelectionController::OnSelectionEmpty(bool empty) {
   if (selection_empty_ == empty)
     return;
   selection_empty_ = empty;
-  ResetCachedValuesIfInactive();
+  ForceNextUpdateIfInactive();
 }
 
 bool TouchSelectionController::Animate(base::TimeTicks frame_time) {
   if (active_status_ == INSERTION_ACTIVE)
     return insertion_handle_->Animate(frame_time);
 
   if (active_status_ == SELECTION_ACTIVE) {
     bool needs_animate = start_selection_handle_->Animate(frame_time);
     needs_animate |= end_selection_handle_->Animate(frame_time);
     return needs_animate;
@@ skipping 102 matching lines @@
 }
 
 float TouchSelectionController::GetTapSlop() const {
   return tap_slop_;
 }
 
 void TouchSelectionController::ShowInsertionHandleAutomatically() {
   if (activate_insertion_automatically_)
     return;
   activate_insertion_automatically_ = true;
-  ResetCachedValuesIfInactive();
+  ForceNextUpdateIfInactive();
 }
 
 void TouchSelectionController::ShowSelectionHandlesAutomatically() {
   if (activate_selection_automatically_)
     return;
   activate_selection_automatically_ = true;
-  ResetCachedValuesIfInactive();
+  ForceNextUpdateIfInactive();
 }
 
 void TouchSelectionController::OnInsertionChanged() {
   DeactivateSelection();
 
   if (response_pending_input_event_ == TAP && selection_empty_ &&
       !show_on_tap_for_empty_editable_) {
     HideAndDisallowShowingAutomatically();
     return;
   }
@@ skipping 95 matching lines @@
     return;
   DCHECK(start_selection_handle_);
   DCHECK(end_selection_handle_);
   LogSelectionEnd();
   start_selection_handle_->SetEnabled(false);
   end_selection_handle_->SetEnabled(false);
   active_status_ = INACTIVE;
   client_->OnSelectionEvent(SELECTION_CLEARED);
 }
 
-void TouchSelectionController::ResetCachedValuesIfInactive() {
-  if (active_status_ != INACTIVE)
-    return;
-  start_ = SelectionBound();
-  end_ = SelectionBound();
-  start_orientation_ = TouchHandleOrientation::UNDEFINED;
-  end_orientation_ = TouchHandleOrientation::UNDEFINED;
+void TouchSelectionController::ForceNextUpdateIfInactive() {
+  if (active_status_ == INACTIVE)
+    force_next_update_ = true;
 }
 
 gfx::Vector2dF TouchSelectionController::GetStartLineOffset() const {
   return ComputeLineOffsetFromBottom(start_);
 }
 
 gfx::Vector2dF TouchSelectionController::GetEndLineOffset() const {
   return ComputeLineOffsetFromBottom(end_);
 }
 
@@ skipping 21 matching lines @@
     base::TimeDelta duration = base::TimeTicks::Now() - selection_start_time_;
     UMA_HISTOGRAM_CUSTOM_TIMES("Event.TouchSelection.WasDraggedDuration",
                                duration,
                                base::TimeDelta::FromMilliseconds(500),
                                base::TimeDelta::FromSeconds(60),
                                60);
   }
 }
 
 }  // namespace ui