SI-8010 Fix regression in erasure double definition checks

Calls to `Symbol#info` during scope iteration considered harmful.

Looks like calling `info` during this Scope iteration is triggering
the ExplicitOuter info transformer, which "makes all super accessors
and modules in traits non-private, mangling their names.". This name
change necessitates a rehashing of the owning scope, which I suspect
is enough to corrupt the ScopeEntry-s being traversed in
`checkNoDeclaredDoubleDefs`.

The upshot was that we encountered the same symbol twice, which was
reported as being a double-definition.

This problem only showed up after 086702d8a74, which did nothing
worse then change the order in which `{e, e1}.sym.info` were
forced.

I inspected SymbolPairs/OverridingPairs which *appear* to be immune
as they only test flags during scope iteration; infos are not used
until later, at which point we're iterating a temporary scope that
isn't part of the type of the owner of the symbols.
Merge pull request #3209 from dotta/SI-7982-on-2.10.x

 make askLoadedType unload arguments out of the PC by default,
SI-7995 completion imported vars and vals

Imported member vals and vars were always marked inaccessible, even
if referencing them at the location of the completion is valid in code.
The accessible flag is now set accordingly to the accessibility of the getter.
SI-8029 Avoid multi-run cyclic error with companions, package object

The bug report suggests this problem only became visible in the
IDE *after* 2.10.3, but I tested an IDE with exactly 2.10.3 and
saw the same problem.

In fact, my test case fails as far back as 2.10.0. I suspect the
problem showed up after 816cecf9a9, which checks that pairs of
companion symbols are codefined eagerly in Namers.

This commit modifies the check of `rawInfo ne NoType`
in `isCoDefinedWith` to avoid triggering adaptation of types from
the previous run. I'm not sure of the precise intent of that check.
I looked at c9861cd198 (genesis of isCoDefinedWith). Before that we
get back to 3761cb4b3a1 (the dawn of Subversion.)
[nomaster] better error messages for various macro definition errors

backport of 1d3ec4e708154ec05554f540d7d68ed55dc12426
Merge pull request #3232 from xeno-by/topic/macro-error-messages-210x

[nomaster] better error messages for various macro definition errors
[backport] SI-7439 Avoid NPE in `isMonomorphicType` with stub symbols.

`originalInfo` can return null for stub symbols; deal with that
as we used to before a regression in 016bc3db.

After this change, we can once again delete A_1.class and still compile
code instantiating B_1. (A_1 is only referred to in a method signature
of B_1 which is not called from our code.)

	scala> new B_1
	warning: Class A_1 not found - continuing with a stub.
	res0: B_1 = B_1@5284b8f9

In practice, this situation arises when someone uses a third
party class that was compiled against other libraries not avaialable
on the current compilation classpath.

(cherry picked from commit a95432168204964e4f6c4571e781559c1640f2d8)
Merge pull request #3223 from retronym/ticket/8010-2.10.x

SI-8010 Fix regression in erasure double definition checks
Merge pull request #3230 from retronym/backport/7439

[backport] SI-7439 Avoid NPE in `isMonomorphicType` with stub symbols.
SI-8050 [Avian] Skip instrumented tests

Instrumentation is (currently) not supported on Avian.
This causes
- tests instrumented/InstrumentationTest.scala and
- instrumented/inline-in-constructors
to fail.

Let's skip these tests on Avian.
Merge pull request #3229 from retronym/ticket/8029

SI-8029 Avoid multi-run cyclic error with companions, package object
SI-8019 Make Publisher check PartialFunction is defined for Event

Reactions are PartialFunctions, so if events come through
indiscriminately that the listener is not defined for, errors occur. Eg:

--
Exception in thread "AWT-EventQueue-0" scala.MatchError: FocusGained(scala.swing wrapper scala.swing.TextField
--

A Coursera thread with people affected by this issue:

https://class.coursera.org/reactive-001/forum/thread?thread_id=1315
Merge pull request #3244 from rtyley/si-8019-swing-publisher-check-pf-defined

SI-8019 Make Publisher check PartialFunction is defined for Event
Merge pull request #3222 from skyluc/issue/completion-import-vals-210-7995

SI-7995 completion imported vars and vals
SI-7912 Be defensive calling `toString` in `MatchError#getMessage`

Otherwise, objects with exception-throwing `toString` lead to a
cascading error far removed from the originally failed match.
SI-8060 Avoid infinite loop with higher kinded type alias

The `dealiasLocals` map was assuming that:

    tp.isAliasType implies (tp.dealias ne tp)

This isn't true if `!typeParamsMatchArgs`.

This commit avoids the infinite loop by checking whether or not
dealiasing progresses.
Do not distribute partest and its dependencies.
Remove unused android test and corresponding license.
Remove docs/examples; they reside at scala/scala-dist
Add attribution for Typesafe.

This was agreed on a while ago, but not yet implemented.