Marshal.load: do not call the proc until strings have their encoding

	Ref: https://bugs.ruby-lang.org/issues/18141
	---
	 marshal.c                             |  7 +++-
	 spec/ruby/core/marshal/shared/load.rb | 62 +++++++++++++++++++++++------------
	 test/ruby/test_marshal.rb             | 17 ++++++++++
	 3 files changed, 64 insertions(+), 22 deletions(-)

	marshal.c: don't call the proc with partially initialized objects.
	 (#4866)

	For cyclic objects, it requires to keep a st_table of the partially
	initialized objects.
	---
	 marshal.c                             | 75 ++++++++++++++++++++---------------
	 spec/ruby/core/marshal/shared/load.rb | 75 ++++++++++++++++++++---------------
	 test/ruby/test_marshal.rb             | 12 ++++++
	 3 files changed, 97 insertions(+), 65 deletions(-)

	spec/ruby/core/process/clock_getres_spec.rb: skip on Android

	in the same way as FreeBSD and OpenBSD.
	I guess that the spec makes too strong assumption.

	Try to avoid random failures on clock_getres_spec.rb

	This spec fails too often
	https://github.com/ruby/ruby/runs/529546249
	https://github.com/ruby/ruby/runs/524933256

	Show failed times

	Remove Process.clock_getres "matches the resolution in practice"
	 specs

	* Almost all platforms return incorrect values for Process.clock_getres,
	  it should be removed: https://bugs.ruby-lang.org/issues/16740

	Skip Process#clock_getres specs on Android

	... just like AIX and OpenBSD.

	Update to ruby/spec@d394dfd

	spec/ruby/core/process/clock_getres_spec.rb: lax the resolution limit

	Android is Linux, but the clock resolution is 10 milliseconds.
	I think that 1 microsecond is too strict for embedded environment.
	This change laxes the limit to 10 milliseconds.

	Disable deprecation warning by the default [Feature #16345]

	And `-w` option turns it on.

Under some Ext4 filesystem settings, a timestamp is limited up to
0x37fffffff (2446-05-10).

https://ext4.wiki.kernel.org/index.php/Ext4_Disk_Layout#Inode_Timestamps
> Therefore, timestamps should not overflow until May 2446.

Actually the spec fails under one of our CI environments, like:

```
1)
File.utime allows Time instances in the far future to set mtime and atime FAILED
Expected 2446 == 559444
to be truthy but was false
```
https://rubyci.org/logs/rubyci.s3.amazonaws.com/arch/ruby-master/log/20200208T180002Z.fail.html.gz

[Backport #16771]

This reverts commit 0d24fb774d84d4a99454ce10fd343da00049a588.

	Update to ruby/spec@cc7b9e5

	Fixed yday and wday with timezone [Bug #17024]

Previously, if an object has a singleton class, and you call
Object#method on the object, the resulting string would include
the object's singleton class, even though the method was not
defined in the singleton class.

Change this so the we only show the singleton class if the method
is defined in the singleton class.

Fixes [Bug #15608]

(cherry picked from commit e02bd0e713ef920e6d12c27f16548f48ec5c2cf0)

[Bug #16406]