HashMap: Remove support for alt-hashing.
This approach has been abandoned in OpenJdk8 (in favour of tree-ifying
when the number of collisions for a given key is large). Given that :
(1) Alt-hashing has always been disabled on Android (the threshold
was Integer.MAX_VALUE).
(2) The OpenJdk8 changes are fairly extensive.
We revert to what's essentially the Android M implementation of HashMap;
always using a secondary hash, always ignoring the load factor and starting
with an initial size of 4.
The Hashtable implementation has been left untouched, except for the
removal of effectively dead alt-hashing code.
bug: 28082128
Change-Id: I12d225d9dbf52e6941864093eefdfb2d60989364
7 files changed
