Reduce max suggestion to show to 2.

- since we now either have 1 or 2 suggestions, putting most layout
configuration in the xml instead of dynamically setting it in code.
- remove the suggestion header
- vertical center align the suggestion title text for 2 cards to make
the card with single line looks better.
- tint all suggestions icons.

Change-Id: I0130f15d530264e164e5afd7c091f165a4a6adc2
Fixes: 70573674
Fixes: 73293989
Fixes: 64986736
Test: visual and make RunSettingsRoboTests

src/com/android/settings/dashboard/DashboardData.java

@@ -41,7 +41,7 @@ import java.util.Objects;
  */
 public class DashboardData {
     public static final int POSITION_NOT_FOUND = -1;
-    public static final int MAX_SUGGESTION_COUNT = 4;
+    public static final int MAX_SUGGESTION_COUNT = 2;
 
     // stable id for different type of items.
     @VisibleForTesting
@@ -443,4 +443,4 @@ public class DashboardData {
         }
     }
 
-}
+}