launcher: refactoring variables into arrays

There are a lot of variables that can be merged together into arrays
following some optimizations done in other places.

Bug: 191879424
Test: checking cell size and extra space in dumpsys
Change-Id: I1d73fbb5da2df2345ced7f46df5bae5d75d9d6b1

src/com/android/launcher3/Partner.java

@@ -142,7 +142,7 @@ public class Partner {
         }
 
         if (iconSize > 0) {
-            inv.iconSize = iconSize;
+            inv.iconSize[InvariantDeviceProfile.INDEX_DEFAULT] = iconSize;
         }
     }
 }