Track search KeyEvents in SearchDialog.

This fixes the bug preventing switching between global and in-app search,
and also enables long press for voice search (I think).

Bug: 2127442
Change-Id: I045a0f7b2c797c016191709a3983b6b33fc6186e
diff --git a/core/java/android/app/SearchDialog.java b/core/java/android/app/SearchDialog.java
index 92515ae..869b354 100644
--- a/core/java/android/app/SearchDialog.java
+++ b/core/java/android/app/SearchDialog.java
@@ -736,7 +736,8 @@
             return false;
         }
 
-        if (keyCode == KeyEvent.KEYCODE_SEARCH) {
+        if (keyCode == KeyEvent.KEYCODE_SEARCH && event.getRepeatCount() == 0) {
+            event.startTracking();
             // Consume search key for later use.
             return true;
         }