[runtime] Avoid joining attached threads. Fixes #19343.
[Http]: Only recycle ServicePoints from the idle timer (fixes #19823).

Thanks a lot for Martin Potter to find and report the race condition
which was causing the problem.

ServicePointManager.RecycleServicePoints() was a left-over from the
old times when we didn't have an idle-timer based approach.
[System.Net.Http]: Always add "Content-Length" in HttpClientHandler.SendAsync().

This has been reported on the forums:
http://forums.xamarin.com/discussion/17770/length-required-error-in-http-post-since-latest-release
[Http]: Cosmetic, remove some dead code.

The is no reason to ever invoke the callback on the ThreadPool,
it would in fact only cause trouble.

Marek's commit db92449f was correct, I removed the commented out
code and the no longer used method.
[mcs] Flow analysis of binary expressions not using logical operators. Fixes #20515
[mcs] Inflate nested pointer containers too.
[Http]: Fix a potential race condition in the WebConnectionGroup's connection list.

Remove the "ConnectionState" from the connection list before closing the connection,
this should avoid ServicePoint.SendRequest() ever crashing with a NullReferenceException
due to getting a null return value from WebConnectionGroup.GetConnection().
[arm] Fix OP_ATOMIC_CAS_I4.
Tarball: include System.Security.dll and System.Configuration.dll in monolite directory
Merge pull request #1105 from tpokorra/TarballIncludeMoreDllsInMonoLite_3.6

Tarball: include System.Security.dll and System.Configuration.dll in monolite directory, branch 3.6.0
[System.ComponentModel] BindingList.ListChanged now attempts to provide a PropertyDescriptor when possible.
BindingList subscribes to PropertyChanged events of eligible contained objects. Iff the PropertyName provided is valid,
the list event's ListChangedEventArgs will also contain a PropertyDescriptor.

This is to match MS behavior.
[aot] Fix the decoding of MonoJitInfo. Fixes #16439.
[runtime] Rewrite MemoryMappedFile to support named mappings.
[runtime] Fix share/private flags when doing file mmap.
[System.Core] Add new tests for MemoryMappedFile.
[runtime] Add a workaround to file-mmap-posix.c to fix the android build.
Silence a warning in file-mmap-posix.c.
[runtime] Don't perform double accounting of offset for named memory segments. Fixes #20591
[runtime] Define DEFFILEMODE to 0666 if not defined.
[runtime] Make it possible to create views to magic zero size files such as /dev/zero. Fixes #19460