third_party/protobuf: Update to HEAD (83d681ee2c)

third_party/protobuf/CHANGES.txt

+2016-09-23 version 3.1.0 (C++/Java/Python/PHP/Ruby/Objective-C/C#/JavaScript/Lite)
+  General
+  * Proto3 support in PHP (alpha).
+  * Various bug fixes.
+
+  C++
+  * Added MessageLite::ByteSizeLong() that’s equivalent to
+    MessageLite::ByteSize() but returns the value in size_t. Useful to check
+    whether a message is over the 2G size limit that protobuf can support.
+  * Moved default_instances to global variables. This allows default_instance
+    addresses to be known at compile time.
+  * Adding missing generic gcc 64-bit atomicops.
+  * Restore New*Callback into google::protobuf namespace since these are used
+    by the service stubs code
+  * JSON support.
+    * Fixed some conformance issues.
+  * Fixed a JSON serialization bug for bytes fields.
+
+  Java
+  * Fixed a bug in TextFormat that doesn’t accept empty repeated fields (i.e.,
+    “field: [ ]”).
+  * JSON support
+    * Fixed JsonFormat to do correct snake_case-to-camelCase conversion for
+      non-style-conforming field names.
+    * Fixed JsonFormat to parse empty Any message correctly.
+    * Added an option to JsonFormat.Parser to ignore unknown fields.
+  * Experimental API
+    * Added UnsafeByteOperations.unsafeWrap(byte[]) to wrap a byte array into
+      ByteString without copy.
+
+  Python
+  * JSON support
+    * Fixed some conformance issues.
+
+  PHP (Alpha)
+  * We have added the proto3 support for PHP via both a pure PHP package and a
+    native c extension. The pure PHP package is intended to provide usability
+    to wider range of PHP platforms, while the c extension is intended to
+    provide higher performance. Both implementations provide the same runtime
+    APIs and share the same generated code. Users don’t need to re-generate
+    code for the same proto definition when they want to switch the
+    implementation later. The pure PHP package is included in the php/src
+    directory, and the c extension is included in the php/ext directory. 
+   
+    Both implementations provide idiomatic PHP APIs:
+    * All messages and enums are defined as PHP classes.
+    * All message fields can only be accessed via getter/setter.
+    * Both repeated field elements and map elements are stored in containers
+      that act like a normal PHP array.
+  
+    Unlike several existing third-party PHP implementations for protobuf, our
+    implementations are built on a "strongly-typed" philosophy: message fields
+    and array/map containers will throw exceptions eagerly when values of the
+    incorrect type (not including those that can be type converted, e.g.,
+    double <-> integer <-> numeric string) are inserted.
+  
+    Currently, pure PHP runtime supports php5.5, 5.6 and 7 on linux. C
+    extension runtime supports php5.5 and 5.6 on linux.
+  
+    See php/README.md for more details about installment. See
+    https://developers.google.com/protocol-buffers/docs/phptutorial for more
+    details about APIs.
+
+  Objective-C
+  * Helpers are now provided for working the the Any well known type (see
+    GPBWellKnownTypes.h for the api additions).
+  * Some improvements in startup code (especially when extensions aren’t used).
+
+  Javascript
+  * Fixed missing import of jspb.Map
+  * Fixed valueWriterFn variable name
+
+  Ruby
+  * Fixed hash computation for JRuby's RubyMessage
+  * Make sure map parsing frames are GC-rooted.
+  * Added API support for well-known types.
+
+  C#
+  * Removed check on dependency in the C# reflection API.
+
+2016-09-06 version 3.0.2 (C++/Java/Python/Ruby/Objective-C/C#/JavaScript/Lite)
+  General
+  * Various bug fixes.
+
+  Objective C
+  * Fix for oneofs in proto3 syntax files where fields were set to the zero
+    value.
+  * Fix for embedded null character in strings.
+  * CocoaDocs support
+
+  Ruby
+  * Fixed memory corruption bug in parsing that could occur under GC pressure.
+
+  Javascript
+  * jspb.Map is now properly exported to CommonJS modules.
+
+  C#
+  * Removed legacy_enum_values flag.
+
+
+2016-07-27 version 3.0.0 (C++/Java/Python/Ruby/Objective-C/C#/JavaScript/Lite)
+  General
+  * This log only contains changes since the beta-4 release. Summarized change
+    log since the last stable release (v2.6.1) can be found in the github
+    release page.
+
+  Compatibility Notice
+  * v3.0.0 is the first API stable release of the v3.x series. We do not expect
+    any future API breaking changes.
+  * For C++, Java Lite and Objective-C, source level compatibility is
+    guaranteed.  Upgrading from v3.0.0 to newer minor version releases will be
+    source compatible. For example, if your code compiles against protobuf
+    v3.0.0, it will continue to compile after you upgrade protobuf library to
+    v3.1.0.
+  * For other languages, both source level compatibility and binary level
+    compatibility are guaranteed. For example, if you have a Java binary built
+    against protobuf v3.0.0. After switching the protobuf runtime binary to
+    v3.1.0, your built binary should continue to work.
+  * Compatibility is only guaranteed for documented API and documented
+    behaviors. If you are using undocumented API (e.g., use anything in the C++
+    internal namespace), it can be broken by minor version releases in an
+    undetermined manner.
+
+  Ruby
+  * When you assign a string field `a.string_field = "X"`, we now call
+    #encode(UTF-8) on the string and freeze the copy. This saves you from
+    needing to ensure the string is already encoded as UTF-8. It also prevents
+    you from mutating the string after it has been assigned (this is how we
+    ensure it stays valid UTF-8).
+  * The generated file for `foo.proto` is now `foo_pb.rb` instead of just
+    `foo.rb`. This makes it easier to see which imports/requires are from
+    protobuf generated code, and also prevents conflicts with any `foo.rb` file
+    you might have written directly in Ruby. It is a backward-incompatible
+    change: you will need to update all of your `require` statements.
+  * For package names like `foo_bar`, we now translate this to the Ruby module
+    `FooBar`. This is more idiomatic Ruby than what we used to do (`Foo_bar`).
+
+  JavaScript
+  * Scalar fields like numbers and boolean now return defaults instead of
+    `undefined` or `null` when they are unset. You can test for presence
+    explicitly by calling `hasFoo()`, which we now generate for scalar fields.
+
+  Java Lite
+  * Java Lite is now implemented as a separate plugin, maintained in the
+    `javalite` branch. Both lite runtime and protoc artifacts will be available
+    in Maven.
+
+  C#
+  * Target platforms now .NET 4.5, selected portable subsets and .NET Core.
+  * legacy_enum_values option is no longer supported.
+
+2016-07-15 version 3.0.0-beta-4 (C++/Java/Python/Ruby/Objective-C/C#/JavaScript)
+  General
+  * Added a deterministic serialization API for C++. The deterministic
+    serialization guarantees that given a binary, equal messages will be
+    serialized to the same bytes. This allows applications like MapReduce to
+    group equal messages based on the serialized bytes. The deterministic
+    serialization is, however, NOT canonical across languages; it is also
+    unstable across different builds with schema changes due to unknown fields.
+    Users who need canonical serialization, e.g. persistent storage in a
+    canonical form, fingerprinting, etc, should define their own
+    canonicalization specification and implement the serializer using reflection
+    APIs rather than relying on this API.
+  * Added OneofOptions. You can now define custom options for oneof groups.
+      import "google/protobuf/descriptor.proto";
+      extend google.protobuf.OneofOptions {
+        optional int32 my_oneof_extension = 12345;
+      }
+      message Foo {
+        oneof oneof_group {
+          (my_oneof_extension) = 54321;
+          ...
+        }
+      }
+
+  C++ (beta)
+  * Introduced a deterministic serialization API in
+    CodedOutputStream::SetSerializationDeterministic(bool). See the notes about
+    deterministic serialization in the General section.
+  * Added google::protobuf::Map::swap() to swap two map fields.
+  * Fixed a memory leak when calling Reflection::ReleaseMessage() on a message
+    allocated on arena.
+  * Improved error reporting when parsing text format protos.
+  * JSON
+      - Added a new parser option to ignore unknown fields when parsing JSON.
+      - Added convenient methods for message to/from JSON conversion.
+  * Various performance optimizations.
+
+  Java (beta)
+  * File option "java_generate_equals_and_hash" is now deprecated. equals() and
+    hashCode() methods are generated by default.
+  * Added a new JSON printer option "omittingInsignificantWhitespace" to produce
+    a more compact JSON output. The printer will pretty-print by default.
+  * Updated Java runtime to be compatible with 2.5.0/2.6.1 generated protos.
+
+  Python (beta)
+  * Added support to pretty print Any messages in text format.
+  * Added a flag to ignore unknown fields when parsing JSON.
+  * Bugfix: "@type" field of a JSON Any message is now correctly put before
+    other fields.
+
+  Objective-C (beta)
+  * Updated the code to support compiling with more compiler warnings
+    enabled. (Issue 1616)
+  * Exposing more detailed errors for parsing failures. (PR 1623)
+  * Small (breaking) change to the naming of some methods on the support classes
+    for map<>. There were collisions with the system provided KVO support, so
+    the names were changed to avoid those issues.  (PR 1699)
+  * Fixed for proper Swift bridging of error handling during parsing. (PR 1712)
+  * Complete support for generating sources that will go into a Framework and
+    depend on generated sources from other Frameworks. (Issue 1457)
+
+  C# (beta)
+  * RepeatedField optimizations.
+  * Support for .NET Core.
+  * Minor bug fixes.
+  * Ability to format a single value in JsonFormatter (advanced usage only).
+  * Modifications to attributes applied to generated code.
+
+  Javascript (alpha)
+  * Maps now have a real map API instead of being treated as repeated fields.
+  * Well-known types are now provided in the google-protobuf package, and the
+    code generator knows to require() them from that package.
+  * Bugfix: non-canonical varints are correctly decoded.
+
+  Ruby (alpha)
+  * Accessors for oneof fields now return default values instead of nil.
+
+  Java Lite
+  * Java lite support is removed from protocol compiler. It will be supported
+    as a protocol compiler plugin in a separate code branch.
+
 2016-05-16 version 3.0.0-beta-3 (C++/Java/Python/Ruby/Nano/Objective-C/C#/JavaScript)
   General
   * Supported Proto3 lite-runtime in C++/Java for mobile platforms.
   * Any type now supports APIs to specify prefixes other than
     type.googleapis.com
   * Removed javanano_use_deprecated_package option; Nano will always has its own
     ".nano" package.
 
   C++ (Beta)
   * Improved hash maps.
@@ skipping 1162 matching lines @@
     contain extra zeros.
   * Fix Python service CallMethod() implementation.
 
   Other
   * Improved readmes.
   * VIM syntax highlighting improvements.
 
 2008-07-07 version 2.0.0:
 
   * First public release.