Detect generated code of WKT, addressbook and conformance protos

Fix java code according to error prone.

Don't expose gson exceptions in JsonFormat.

Use per-type table to lookup JSON name.

Add missing thread dependency in cmake.

Update comments for setSizeLimit.

Accept regular PHP array for repeated/map setter. Existing map/repeated
field will be swapped by a clean map/repeated field. Then, elements in
the array will be added to the map/repeated field. All elements will be
type checked before adding.

See #2686 for detail.

Cherry-pick changes from javalite branch to also fix Java warnings in the master branch

Make JsonFormat locale independent.

Different fields from different messages can map to the same JSON name
and the original global lookup table is only capable of mapping one of
such fields. This change converts the global table to per-type tables
so fields from different messages won't conflict.

update_failure_list.py: fixed Python "raise" statement.

Ruby: wrap calls to memcpy so that gem is compatible with pre-2.14 glibc

Avoid redundant type casts for oneof bytes fields.

Undef major/minor if they are defined as macro.

Add annotations for deprecated messages in Java

This commit adds a __wrap_memcpy function and a linker flag to use that
in place of memcpy for our Ruby gem C extension. This allows us to
always use the 2.2.5 version of memcpy, making it possible to use the
gem on distributions with pre-2.14 versions of glibc.

Before this change:
$ objdump -T protobuf_c.so | grep memcpy
0000000000000000      DF *UND*  0000000000000000  GLIBC_2.3.4 __memcpy_chk
0000000000000000      DF *UND*  0000000000000000  GLIBC_2.14  memcpy

After:
$ objdump -T protobuf_c.so | grep memcpy
0000000000000000      DF *UND*  0000000000000000  GLIBC_2.2.5 memcpy
0000000000000000      DF *UND*  0000000000000000  GLIBC_2.3.4 __memcpy_chk
0000000000042450 g    DF .text  0000000000000005  Base __wrap_memcpy

This is based on gRPC's solution to a similar problem:
https://github.com/grpc/grpc/blob/5098508d2d41a116113f7e333c516cd9ef34a943/src/core/lib/support/wrap_memcpy.c

This fixes issue #2783.

Method Builder#clone() has been changed to bypass Java 1.6 compiler issue.

This better shows the semantic of the API. For already setted fields,
mergeFromString do replacement for singular fields and appending for
repeated fields.

Removed a stray return statement, causing compilation error.

 optimization and quick workaround to memory leak

Merge pull request #2788 from anandolee/master

Added a header only cc_library target for the protobuf library.

Return uint32 from Log2FloorNonZero64

Add Ruby compatibilty test against 3.0.0.

Handing threading race resolving methods.