Bump protobuf from 3.12.2 to 3.16.0

[dependabot-preview]

Bumps protobuf from 3.12.2 to 3.16.0.

Release notes

Sourced from protobuf's releases.

Protocol Buffers v3.16.0

C++

• Fix compiler warnings issue found in conformance_test_runner #8189 (#8190)
• Fix MinGW-w64 build issues. (#8286)
• [Protoc] C++ Resolved an issue where NO_DESTROY and CONSTINIT are in incorrect order (#8296)
• Fix PROTOBUF_CONSTINIT macro redefinition (#8323)
• Delete StringPiecePod (#8353)
• Fix gcc error: comparison of unsigned expression in '>= 0' is always … (#8309)
• Fix cmake install on iOS (#8301)
• Create a CMake option to control whether or not RTTI is enabled (#8347)
• Fix endian.h location on FreeBSD (#8351)
• Refactor util::Status (#8354)
• Make util::Status more similar to absl::Status (#8405)
• Fix -Wsuggest-destructor-override for generated C++ proto classes. (#8408)
• Refactor StatusOr and StringPiece (#8406)
• Refactor uint128 (#8416)
• The ::pb namespace is no longer exposed due to conflicts.
• Allow MessageDifferencer::TreatAsSet() (and friends) to override previous calls instead of crashing.
• Reduce the size of generated proto headers for protos with string or bytes fields.
• Move arena() operation on uncommon path to out-of-line routine
• For iterator-pair function parameter types, take both iterators by value.
• Code-space savings and perhaps some modest performance improvements in RepeatedPtrField.
• Eliminate nullptr check from every tag parse.
• Remove unused _$name$cached_byte_size fields.
• Serialize extension ranges together when not broken by a proto field in the middle.
• Do out-of-line allocation and deallocation of string object in ArenaString.
• Streamline ParseContext::ParseMessage to avoid code bloat and improve performance.
• New member functions RepeatedField::Assign, RepeatedPtrField::{Add, Assign}.
• Fix undefined behavior warning due to innocuous uninitialization of value on an error path.
• Avoid expensive inlined code space for encoding message length for messages

  = 128 bytes and instead do a procedure call to a shared out-of-line routine.

• util::DefaultFieldComparator will be final in a future version of protobuf. Subclasses should inherit from SimpleFieldComparator instead.

C#

• Add .NET 5 target and improve WriteString performance with SIMD (#8147)

Java

• deps: update JUnit and Truth (#8319)
• Detect invalid overflow of byteLimit and return InvalidProtocolBufferException as documented.
• Exceptions thrown while reading from an InputStream in parseFrom are now included as causes.
• Support potentially more efficient proto parsing from RopeByteStrings.
• Clarify runtime of ByteString.Output.toStringBuffer().

... (truncated)

Commits

• 2dc747c Update PHP release notes and update version to 3.16.0 (#8573)
• debc03d Update protobuf version to 3.16.0-rc2 (#8556)
• 17b0fb9 Make update_version.py compatible with Python 3 (#8555)
• 4aa425c Cherry-pick #8356 into 3.16.x (#8518)
• e8b78f8 Fixed memory leak of Ruby arena objects. (#8465)
• 7689f00 Update protobuf version (#8448)
• 6099c65 Updated CHANGES.txt for 3.16.0 (#8456)
• c934386 Merge pull request #8447 from acozzette/merge-3-15-x
• 6007999 Revert "[C++] Refactor uint128 (#8416)"
• 87aa9ad Merge branch 'master' into 3.15.x
• Additional commits viewable in compare view

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[dependabot-preview]

Superseded by #74.