Rank results that match the prefix of the first word higher

Differentiates the results that match the first word in
the title from matches farther into the title.

Change-Id: I69f9804a51d1c2b0e476b0f082d634b3a598997c
Fixes: 34975472
Test: make RunSettingsRoboTests

src/com/android/settings/search2/InstalledAppResultLoader.java

@@ -207,8 +207,8 @@ public class InstalledAppResultLoader extends AsyncLoader<List<? extends SearchR
      */
     private int getRank(int wordDiff) {
         if (wordDiff < 6) {
-            return 3;
+            return 2;
         }
-        return 4;
+        return 3;
     }
 }