Track const reference evaluate results

Previously, the results of handleShift() handleBinaryCommon() and
handleUnary() were not being used to update is_valid_ which allowed for
some overflows to go unnoticed.

Bug: 175990072
Test: atest aidl_unittests aidl_integration_test
Test: aidl_parser_fuzzer tests/corpus/const_overflow
Change-Id: I6e1f8c498ed132ada409335b961a631355fa9427
2 files changed