No sound produced on global actions dialog pops up if no vibrator is present.

1. If the global gesture to enable accessibility is enabled there should
   be a haptic or auditory feedback after the global actions dialog pops up
   as a result of a long press on power. On devices with no vibrator an
   attempt to vibrate was performed evne if not hardware support exists
   As a result no sound was played because the it was assumed a haptic
   feedback was provided.

bug:7324903

Change-Id: Ic76db232d761a2899c1ca5f59ca55ff15ae575dd

Author: sganov

policy/src/com/android/internal/policy/impl/PhoneWindowManager.java

@@ -4302,6 +4302,9 @@ private boolean isGlobalAccessibilityGestureEnabled() {
     }
 
     public boolean performHapticFeedbackLw(WindowState win, int effectId, boolean always) {
+        if (!mVibrator.hasVibrator()) {
+            return false;
+        }
         final boolean hapticsDisabled = Settings.System.getIntForUser(mContext.getContentResolver(),
                 Settings.System.HAPTIC_FEEDBACK_ENABLED, 0, UserHandle.USER_CURRENT) == 0;
         if (!always && (hapticsDisabled || mKeyguardMediator.isShowingAndNotHidden())) {