Fix single-stepping resume mode in the interpreter.

Fix single-stepping resume mode in the interpreter.

(cherry-picked from master)

When a resume attempt is cancelled due to other pending request make sure
the old native resume PC is cleared. Otherwise the JIT code cache may be
re-entered with mismatching Dalvik PC.

Also fix a code bloat problem where single-step count is not set properly
after executing a return instruction.

BUG: 5208786

Change-Id: I54775215b11eae29ccdb6111dc0fdfa99e41e08d