Update Settings search result unique ids

- SearchResult stableIds are now DocIds from the database
- DocIds are data reference key's hash, when the key is not
empty or null
- Otherwise, DocIds are a hashcode from a set of fields.

Change-Id: Id36f7bf4ceaaa3a2bd326ecafbfe97fd0b247df2
Fixes: 37327194
Test: make RunSettingsRoboTest

tests/robotests/src/com/android/settings/search/InlineSwitchViewHolderTest.java

@@ -110,13 +110,14 @@ public class InlineSwitchViewHolderTest {
 
     private SearchResult getSearchResult() {
         SearchResult.Builder builder = new SearchResult.Builder();
-        builder.addTitle(TITLE)
-                .addSummary(SUMMARY)
-                .addRank(1)
-                .addPayload(new InlineSwitchPayload("", 0, null, null))
+        builder.setTitle(TITLE)
+                .setSummary(SUMMARY)
+                .setRank(1)
+                .setPayload(new InlineSwitchPayload("", 0, null, null))
                 .addBreadcrumbs(new ArrayList<>())
-                .addIcon(mIcon)
-                .addPayload(mPayload);
+                .setIcon(mIcon)
+                .setPayload(mPayload)
+                .setStableId(TITLE.hashCode());
 
         return builder.build();
     }