Remove usage of ScopedLocalFrame because it is not needed

ScopedLocalFrame is needed only when we need to reserve a large
number of JNI local references. The local references in the corresponding
code is small (below the default limit of 15).

Furthermore, using ScopedLocalFrame itself can be problematic:
it is excessive (reserves 128 entries out of total 512), and does
not check for errors.

Bug: 37969574
Test: Manual
Change-Id: Ia460fe9dd61ce91c940f64a980ec7256774d2fff