* Added -Wextra and -Wshorten-64-to-32 and fixed resulting errors.
* Disable -Wshorten-32-to-64 since Kokoro is missing Clang.
* Fixed -Wextra warnings for gcc.
* Reordered UPB_UNUSED() to come after declarations.
* Added another -pedantic fix and log CC version.
* Fix compile error and conditionally run use_bazel.sh.
* Moved set -e after use_bazel.sh.
* Fixed typo in conditional.
* Simplified epoch day algorithm.
* A nicer version that divides by 2048, thanks to Gerben. for the suggestion.
* A little less cleverness, for the sake of readability.
* A bit more tweaking for readability.
* Updated CMake copy.
* Add tests for proto2
* Fix ignore unknown enum value
* Fix CheckConsistency
* Add note to mention clear field for unknown enum value
* Update Comment
* Fix generated test
* Fix generated test
* Added support for proto3 optional to defs.
* Added proto3 optional support. Untested at the moment.
* Changes to support proto3 optional.
* Fixed real oneof count for messages with no fields.
* Fixed compile error and test.
* Added comment about why I'm commenting out the assert.