THRIFT-926. cpp: TMemoryBuffer: Uphold the strong exception safety guarantee

Previously, if we had a realloc failure when growing a TMemoryBuffer, we
would leave the buffer in an invalid state (bufferSize_ would reflect
the desired size, rather than the actual size).  Now, we make no change
to any member variables if realloc fails.

git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@1005165 13f79535-47bb-0310-9956-ffa450edef68
1 file changed