6e8c48dc5 Add const to methods that do not modify the object for which it is called (practicalswift)
Pull request description:
Tree-SHA512: a6888111ba16fb796e320e60806e1a77d36f545989b5405dc7319992291800109eab0b8e8c286b784778f41f1ff5289e7cb6b4afd7aec77f385fbcafc02cffc1
5113474 wallet: Use CDataStream.data() (Wladimir J. van der Laan)
e2300ff bench: Use CDataStream.data() (Wladimir J. van der Laan)
adff950 dbwrapper: Use new .data() method of CDataStream (Wladimir J. van der Laan)
a2141e4 streams: Remove special cases for ancient MSVC (Wladimir J. van der Laan)
af4c44c streams: Add data() method to CDataStream (Wladimir J. van der Laan)
Dbwrapper used GetSerializeSize() to compute the size of the buffer
to preallocate. For some cases (specifically: CCoins) this requires
a costly compression call. Avoid this by just using fixed size
preallocations instead.
Given that in default GetSerializeSize implementations created by
ADD_SERIALIZE_METHODS we're already using CSizeComputer(), get rid
of the specialized GetSerializeSize methods everywhere, and just use
CSizeComputer. This removes a lot of code which isn't actually used
anywhere.
For CCompactSize and CVarInt this actually removes a more efficient
size computing algorithm, which is brought back in a later commit.
Pass parent wrapper directly instead of obfuscation key. This
makes it possible for other databases which re-use this code
to use other properties from the database.
Add a namespace dbwrapper_private for private functions to be used
only in dbwrapper.h/cpp and dbwrapper_tests.
Using throw() specifications in function signatures is not only
not required in C++, it is considered deprecated for
[various reasons](https://stackoverflow.com/questions/1055387/throw-keyword-in-functions-signature).
It is not implemented by any of the common C++ compilers. The usage is
also inconsistent with the rest of the source code.
