Implementated corner passthrough when touch exploration

 controller is on. 

If the user presses and holds the bottom right or left
 corner of the screen past a time delay, an earcon will
 sound, and then any subsequent fingers added onto the
 screen will send touch events as normal (passed through)
 as long as one finger is at a corner of the screen. Once
 the finger on the corner of the screen has lifted, then
 nothing will happen until all the fingers on the screen
 have been lifted.

UPDATE: Added earcons (short sound notifications) to
 indicate to the user if they have moved their finger off
 the screen or onto the screen or if they are in passthrough.
BUG=396310

Review URL: https://codereview.chromium.org/410783002

Cr-Commit-Position: refs/heads/master@{#289468}
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@289468 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 4 insertions, 1 deletions

diff --git a/ash/ash_touch_exploration_manager_chromeos.h b/ash/ash_touch_exploration_manager_chromeos.h
index d6ca881..bce2a52 100644
--- a/ash/ash_touch_exploration_manager_chromeos.h
+++ b/ash/ash_touch_exploration_manager_chromeos.h
@@ -33,9 +33,12 @@ class ASH_EXPORT AshTouchExplorationManager
       AccessibilityNotificationVisibility notify) OVERRIDE;
 
   // TouchExplorationControllerDelegate overrides:
-  virtual void PlayVolumeAdjustSound() OVERRIDE;
   virtual void SetOutputLevel(int volume) OVERRIDE;
   virtual void SilenceSpokenFeedback() OVERRIDE;
+  virtual void PlayVolumeAdjustEarcon() OVERRIDE;
+  virtual void PlayPassthroughEarcon() OVERRIDE;
+  virtual void PlayExitScreenEarcon() OVERRIDE;
+  virtual void PlayEnterScreenEarcon() OVERRIDE;
 
  private:
   void UpdateTouchExplorationState();