Reducing method count by eliminating synthetic accessors

Elimates 304 methods based on dex analysis

The java compiler generates sythetic accessor methods for all private
fields, methods and contructors accessed from inner classes. By marking them
package-private and @Thunk instead, sythentic accessor methods are no
longer needeed. These annotated elements should be treated as private.

Change-Id: Id0dc2c92733474250d8ff12fa793d3a8adeb1f26