Reuse DexCache and ClassLoader handles in inliner.

Measured memory usage with heaptrack for a large app:
  Before:
    bytes allocated in total (ignoring deallocations): 3.14GB
    calls to allocation functions: 8130596
  After:
    bytes allocated in total (ignoring deallocations): 3.12GB
    calls to allocation functions: 7750377

Test: testrunner.py --host
Bug: 34053922
Change-Id: I1ad7aaffccc6527cd4f409ca8fca75bab8d7439a
1 file changed