* Rolled forward again with "Updated upb from defcleanup branch..."

Revert "Revert "Updated upb from defcleanup branch and modified Ruby to use it (#5539)" (#5848)"

This reverts commit 1568deab.

* A few more merge fixes.

* Updated for defcleanup2 branch.

* Fixed upb to define upb_decode().

* Fixed names of nested messages.

* Revert submodule.

* Set -std=gnu90 and fixed warnings/errors.

Some of our Kokoro tests seem to run with this level of warnings,
and the source strives to be gnu90 compatible.  Enforcing it for
every build removes the possibility of some errors showing up in
Kokoro/Travis tests only.

* Fixed remaining warnings with gnu90 mode.

I tried to match warning flags with what Ruby appears to do
in our Kokoro tests.

* Initialize values registered by rb_gc_register_address().

* Fixed subtle GC bug.

We need to initialize this marked value before creating the instance.

* Truly fix the GC bug.

* Updated upb for mktime() fix.

* Removed XOPEN_SOURCE as we are not using strptime().

* Removed fixed tests from the conformance failure list for Ruby.

* Fixed memory error related to oneof def names.

* Picked up new upb changes re: JSON printing.

* Uncomment concurrent decoding test.

* support hashes for struct initalizers

* convert hash keys to string

* update tests

* add extra asserts

value_field_typeclass should be a enum module, not EnumDescriptor
object.

Also expanding tests for enum valued maps.

Fixes #4580
Signed-off-by: Sorah Fukumori <her@sorah.jp>

This reverts commit 37581380.

* add frozen checks

* Use rb_check_frozen

* Correct assertion on frozen error message

The second argument for the method assert_raise is the message
to show when the assertion fails. It does not check the error
object's message.
Add an additional assertion that does check the error's message.

* do frozen check first

* add more descriptive error messages to init methods

* add type errors test to Makefile.am

Revert "Revert "Enable the ignore_unknown_field option in the Ruby unmarshal options" (#5511)" (#5533)

* Revert "Revert "Enable the ignore_unknown_field option in the Ruby unmarshal options" (#5511)"

This reverts commit be1716a6.

* Separate ruby conformance test on Mac

* Fix shell syntax

* Fix test

This adds the ability for the MRI Ruby library to optionally pass in a
ignore_unknown_fields option when decoding JSON. The functionality was
added upstream in upb, this change exposes that option.

* Replace assert_true/assert_false with assert, because they are not provided in newer version of test/unit

* Use rescue to handle exception subclass

* Commented out the require that caused gc_test failure.

* Commented out test

* Fix typo

This change only adds basic proto2 support without advanced features
like extensions, custom options, maps, etc.

The protoc binary now generates ruby code for proto2 syntax.
However, for now, it is restricted to proto2 files without advanced features
like extensions, in which case it still errors out.

This change also modifies the DSL to add proto messages to the DescriptorPool.
There is a new DSL Builder#add_file to create a new FileDescriptor. With this,
the generated ruby DSL looks something like:

Google::Protobuf::DescriptorPool.generated_pool.build do
  add_file "test.proto" do
    add_message "foo" do
      optional :val, :int32, 1
    end
  end
end

* Add continuous test for ruby 2.3, 2.4 and 2.5

* Change ruby 2.5 to 2.5.0

* No need to provide argument to rb_funcall when argc is 0

* Fix tests for ruby 2.5

* Use rescue instead of assert_raise to accept subclass of error

* Add continuous test for ruby 2.3, 2.4 and 2.5

* Change ruby 2.5 to 2.5.0

* No need to provide argument to rb_funcall when argc is 0

* Fix tests for ruby 2.5

* Use rescue instead of assert_raise to accept subclass of error

* This allows for ruby code to catch and handle Protobuf
    TypeErrors separately from the standard Ruby TypeError

  * Maintains backwards compatibility by having the new
    Google::Protobuf::TypeError inherit from the base
    TypeError. Any code that was catching TypeError should
    continue to work.

This makes it behave the same way as the other implementations.
It is also nice to always encode an empty message as {}.

This makes the frame stack per-parser, and per-thread.  Fixes #3250

This makes the frame stack per-parser, and per-thread.  Fixes #3250

* Fixed a bunch of Ruby conformance errors.

* Fixed some more Ruby conformance errors in JSON.

Usage: Message.encode_json(m, emit_defaults: true)
Message fields that are nil will still not appear in the encoded JSON.

* Down-integrate internal changes to github.

* Update conformance test failure list.

* Explicitly import used class in nano test to avoid random test fail.

* Update _GNUC_VER to use the correct implementation of atomic operation
on Mac.

* maps_test.js: check whether Symbol is defined before using it (#2524)

Symbol is not yet available on older versions of Node.js and so this
test fails with them. This change just directly checks whether Symbol is
available before we try to use it.

* Added well_known_types_embed.cc to CLEANFILES so that it gets cleaned up

* Updated Makefile.am to fix out-of-tree builds

* Added Bazel genrule for generating well_known_types_embed.cc

In pull request #2517 I made this change for the CMake and autotools
builds but forgot to do it for the Bazel build.

* Update _GNUC_VER to use the correct implementation of atomic operation on Mac.

* Add new js file in extra dist.

* Bump version number to 3.2.0

* Fixed issue with autoloading - Invalid paths (#2538)

* PHP fix int64 decoding (#2516)

* fix int64 decoding

* fix int64 decoding + tests

* Fix int64 decoding on 32-bit machines.

* Fix warning in compiler/js/embed.cc

embed.cc: In function ‘std::string CEscape(const string&)’:
embed.cc:51:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int i = 0; i < str.size(); ++i) {
                                ^

* Fix include in auto-generated well_known_types_embed.cc

Restore include style fix (e3da722b) that has been trampled by
auto-generation of well_known_types_embed.cc

* Fixed cross compilations with the Autotools build

Pull request #2517 caused cross compilations to start failing, because
the js_embed binary was being built to run on the target platform
instead of on the build machine. This change updates the Autotools build
to use the AX_PROG_CXX_FOR_BUILD macro to find a suitable compiler for
the build machine and always use that when building js_embed.

* Minor fix for autocreated object repeated fields and maps.

- If setting/clearing a repeated field/map that was objects, check the class
  before checking the autocreator.
- Just to be paranoid, don’t mutate within copy/mutableCopy for the autocreated
  classes to ensure there is less chance of issues if someone does something
  really crazy threading wise.
- Some more tests for the internal AutocreatedArray/AutocreatedDictionary
  classes to ensure things are working as expected.
- Add Xcode 8.2 to the full_mac_build.sh supported list.

* Fix generation of extending nested messages in JavaScript (#2439)

* Fix generation of extending nested messages in JavaScript

* Added missing test8.proto to build

* Fix generated code when there is no namespace but there is enum definition.

* Decoding unknown field should succeed.

* Add embed.cc in src/Makefile.am to fix dist check.

* Fixed "make distcheck" for the Autotools build

To make the test pass I needed to fix out-of-tree builds and update
EXTRA_DIST and CLEANFILES.

* Remove redundent embed.cc from src/Makefile.am

* Update version number to 3.2.0-rc.1 (#2578)

* Change protoc-artifacts version to 3.2.0-rc.1

* Update version number to 3.2.0rc2

* Update change logs for 3.2.0 release.

* Update php README

* Update upb, fixes some bugs (including a hash table problem). (#2611)

* Update upb, fixes some bugs (including a hash table problem).

* Ruby: added a test for the previous hash table corruption.

Verified that this triggers the bug in the currently released
version.

* Ruby: bugfix for SEGV.

* Ruby: removed old code for dup'ing defs.

* Reverting deployment target to 7.0 (#2618)

The Protobuf library doesn’t require the 7.1 deployment target so
reverting it back to 7.0

* Fix typo that breaks builds on big-endian (#2632)

* Bump version number to 3.2.0

This makes a couple of changes to fix the tests for JRuby 1.7:
- Avoid using assert_false since that assertion seems not to exist in
  older versions
- Disable a test related to respond_to? for JRuby. It's hard to tell
  what is going wrong here but it looks like probably a JRuby bug that
  has been fixed in more recent versions.

* add a repeated field to the tested hash
* also assert that two messages with identical values produce identical hashes

For JSON encoding we provide a new option to decide at
encode time whether to use camelCase or original proto field
names:

  json = MapMessage.encode_json(m, :preserve_proto_fieldnames => true)