Count native allocation for VD against Java heap

There are two parts to VD's native allocation:
1) VD's internal data structure (i.e. groups, paths, etc that make
   up of the VD tree). This structure can change, when a VD is used
   to load a different drawable resource.
2) Two bitmap caches, not both of which will necessarily be allocated
   The size of the bitmap cache depends on canvas matrix and drawable
   bounds, and therefore can often change.

We need to count the native allocation from the above against Java heap.

Bug: 26269056
Change-Id: If833aedcf7f3efe00ea73a41ddccb1b48066ffd8