Backport of SI-6846.

Squashed commit of the following:

commit 55806cc0e6177820c12a35a18b4f2a12dc07bb39
Author: Paul Phillips <paulp@improving.org>
Date:   Wed Dec 19 07:32:19 2012 -0800

    SI-6846, regression in type constructor inference.

    In 658ba1b4e6 some inference was gained and some was lost.
    In this commit we regain what was lost and gain even more.
    Dealiasing and widening should be fully handled now, as
    illustrated by the test case.
    (cherry picked from commit dbebcd509e4013ce02655a2687b27d0967b3650e)

commit e6ef58447d0f4ef6de956fcc03ee283bb9028c02
Author: Paul Phillips <paulp@improving.org>
Date:   Fri Dec 21 15:11:29 2012 -0800

    Cleaning up type alias usage.

    I determined that many if not most of the calls to .normalize
    have no intent beyond dealiasing the type. In light of this I
    went call site to call site knocking on doors and asking why
    exactly they were calling any of

      .normalize
      .widen.normalize
      .normalize.widen

    and if I didn't like their answers they found themselves
    introduced to 'dropAliasesAndSingleTypes', the recursive widener
    and dealiaser which I concluded is necessary after all.

    Discovered that the object called 'deAlias' actually depends
    upon calling 'normalize', not 'dealias'. Decided this was
    sufficient cause to rename it to 'normalizeAliases'.

    Created dealiasWiden and dealiasWidenChain.

    Dropped dropAliasesAndSingleTypes in favor of methods
    on Type alongside dealias and widen (Type#dealiasWiden).
    These should reduce the number of "hey, the type alias doesn't work" bugs.

    (cherry picked from commit 3bf51189f979eb0dd41744ca844fd12dfdaa0dee)

    Conflicts:
    	src/compiler/scala/tools/nsc/interpreter/CompletionOutput.scala

commit c1d8803cea1523f458730103386d8e14324a9446
Author: Paul Phillips <paulp@improving.org>
Date:   Sat Dec 22 08:13:48 2012 -0800

    Shored up a hidden dealiasing dependency.

    Like the comment says:

    // This way typedNew always returns a dealiased type. This
    // used to happen by accident for instantiations without type
    // arguments due to ad hoc code in typedTypeConstructor, and
    // annotations depended on it (to the extent that they worked,
    // which they did not when given a parameterized type alias
    // which dealiased to an annotation.) typedTypeConstructor
    // dealiases nothing now, but it makes sense for a "new" to
    // always be given a dealiased type.

    PS:
    Simply running the test suite is becoming more difficult all
    the time. Running "ant test" includes time consuming activities
    of niche interest such as all the osgi tests, but test.suite
    manages to miss the continuations tests.
    (cherry picked from commit 422f461578ae0547181afe6d2c0c52ea1071d37b)

commit da4748502792b260161baa10939554564c488051
Author: Paul Phillips <paulp@improving.org>
Date:   Fri Dec 21 12:39:02 2012 -0800

    Fix and simplify typedTypeConstructor.

    Investigating the useful output of devWarning (-Xdev people,
    it's good for you) led back to this comment:

      "normalize to get rid of type aliases"

    You may know that this is not all the normalizing does.
    Normalizing also turns TypeRefs with unapplied arguments
    (type constructors) into PolyTypes. That means that when
    typedParentType would call typedTypeConstructor it would
    find its parent had morphed into a PolyType. Not that it
    noticed; it would blithely continue and unwittingly discard
    the type arguments by way of appliedType (which smoothly
    logged the incident, thank you appliedType.)

    The simplification of typedTypeConstructor:

    There was a whole complicated special treatment of AnyRef
    here which appears to have become unnecessary. Removed special
    treatment and lit a candle for regularity.

    Updated lots of tests regarding newly not-so-special AnyRef.
    (cherry picked from commit 394cc426c1ff1da53146679b4e2995ece52a133e)

commit 1f3c77bacb2fbb3ba9e4ad0a8a733e0f9263b234
Author: Paul Phillips <paulp@improving.org>
Date:   Fri Dec 21 15:06:10 2012 -0800

    Removed dead implementation.

    Another "attractive nuisance" burning off time until I
    realized it was commented out.
    (cherry picked from commit ed40f5cbdf35d09b02898e9c0950b9bd34c1f858)

18 files changed, 21 insertions, 21 deletions

diff --git a/test/files/scalap/abstractClass/result.test b/test/files/scalap/abstractClass/result.test
index 9163346fc6..ef1daac23d 100644
--- a/test/files/scalap/abstractClass/result.test
+++ b/test/files/scalap/abstractClass/result.test
@@ -1,4 +1,4 @@
-abstract class AbstractClass extends java.lang.Object {
+abstract class AbstractClass extends scala.AnyRef {
   def this() = { /* compiled code */ }
   def foo : scala.Predef.String
 }
diff --git a/test/files/scalap/abstractMethod/result.test b/test/files/scalap/abstractMethod/result.test
index 90f572f258..40fa02d408 100644
--- a/test/files/scalap/abstractMethod/result.test
+++ b/test/files/scalap/abstractMethod/result.test
@@ -1,4 +1,4 @@
-trait AbstractMethod extends java.lang.Object {
+trait AbstractMethod extends scala.AnyRef {
   def $init$() : scala.Unit = { /* compiled code */ }
   def arity : scala.Int
   def isCool : scala.Boolean = { /* compiled code */ }
diff --git a/test/files/scalap/cbnParam/result.test b/test/files/scalap/cbnParam/result.test
index fbe035d63c..52ecb6ae66 100644
--- a/test/files/scalap/cbnParam/result.test
+++ b/test/files/scalap/cbnParam/result.test
@@ -1,3 +1,3 @@
-class CbnParam extends java.lang.Object {
+class CbnParam extends scala.AnyRef {
   def this(s : => scala.Predef.String) = { /* compiled code */ }
 }
diff --git a/test/files/scalap/classPrivate/result.test b/test/files/scalap/classPrivate/result.test
index 5f2e1cc00e..ab2d40cdaf 100644
--- a/test/files/scalap/classPrivate/result.test
+++ b/test/files/scalap/classPrivate/result.test
@@ -1,7 +1,7 @@
-class ClassPrivate extends java.lang.Object {
+class ClassPrivate extends scala.AnyRef {
   def this() = { /* compiled code */ }
   def baz : scala.Int = { /* compiled code */ }
-  class Outer extends java.lang.Object {
+  class Outer extends scala.AnyRef {
     def this() = { /* compiled code */ }
     private[ClassPrivate] def qux : scala.Int = { /* compiled code */ }
   }
diff --git a/test/files/scalap/classWithExistential/result.test b/test/files/scalap/classWithExistential/result.test
index b8ce005da9..caee3fd6de 100644
--- a/test/files/scalap/classWithExistential/result.test
+++ b/test/files/scalap/classWithExistential/result.test
@@ -1,4 +1,4 @@
-class ClassWithExistential extends java.lang.Object {
+class ClassWithExistential extends scala.AnyRef {
   def this() = { /* compiled code */ }
   def foo[A, B] : scala.Function1[A, B forSome {type A <: scala.Seq[scala.Int]; type B >: scala.Predef.String}] = { /* compiled code */ }
 }
diff --git a/test/files/scalap/classWithSelfAnnotation/result.test b/test/files/scalap/classWithSelfAnnotation/result.test
index df7bd86643..82bbd9e8df 100644
--- a/test/files/scalap/classWithSelfAnnotation/result.test
+++ b/test/files/scalap/classWithSelfAnnotation/result.test
@@ -1,4 +1,4 @@
-class ClassWithSelfAnnotation extends java.lang.Object {
+class ClassWithSelfAnnotation extends scala.AnyRef {
  this : ClassWithSelfAnnotation with java.lang.CharSequence =>
   def this() = { /* compiled code */ }
   def foo : scala.Int = { /* compiled code */ }
diff --git a/test/files/scalap/covariantParam/result.test b/test/files/scalap/covariantParam/result.test
index 2f52f1f28e..f7a3c98966 100644
--- a/test/files/scalap/covariantParam/result.test
+++ b/test/files/scalap/covariantParam/result.test
@@ -1,4 +1,4 @@
-class CovariantParam[+A] extends java.lang.Object {
+class CovariantParam[+A] extends scala.AnyRef {
   def this() = { /* compiled code */ }
   def foo[A](a : A) : scala.Int = { /* compiled code */ }
 }
diff --git a/test/files/scalap/defaultParameter/result.test b/test/files/scalap/defaultParameter/result.test
index 38bf6ac4e3..0c775ea7b5 100644
--- a/test/files/scalap/defaultParameter/result.test
+++ b/test/files/scalap/defaultParameter/result.test
@@ -1,3 +1,3 @@
-trait DefaultParameter extends java.lang.Object {
+trait DefaultParameter extends scala.AnyRef {
   def foo(s : scala.Predef.String) : scala.Unit
-}
\ No newline at end of file
+}
diff --git a/test/files/scalap/implicitParam/result.test b/test/files/scalap/implicitParam/result.test
index 0ea212dda6..a2cfd6092d 100644
--- a/test/files/scalap/implicitParam/result.test
+++ b/test/files/scalap/implicitParam/result.test
@@ -1,4 +1,4 @@
-class ImplicitParam extends java.lang.Object {
+class ImplicitParam extends scala.AnyRef {
   def this() = { /* compiled code */ }
   def foo(i : scala.Int)(implicit f : scala.Float, d : scala.Double) : scala.Int = { /* compiled code */ }
 }
diff --git a/test/files/scalap/packageObject/result.test b/test/files/scalap/packageObject/result.test
index 94c6a01b08..5732d92958 100644
--- a/test/files/scalap/packageObject/result.test
+++ b/test/files/scalap/packageObject/result.test
@@ -1,4 +1,4 @@
-package object PackageObject extends java.lang.Object {
+package object PackageObject extends scala.AnyRef {
   def this() = { /* compiled code */ }
   type A = scala.Predef.String
   def foo(i : scala.Int) : scala.Int = { /* compiled code */ }
diff --git a/test/files/scalap/paramClauses/result.test b/test/files/scalap/paramClauses/result.test
index dc4397386c..3a141e8faf 100644
--- a/test/files/scalap/paramClauses/result.test
+++ b/test/files/scalap/paramClauses/result.test
@@ -1,4 +1,4 @@
-class ParamClauses extends java.lang.Object {
+class ParamClauses extends scala.AnyRef {
   def this() = { /* compiled code */ }
   def foo(i : scala.Int)(s : scala.Predef.String)(t : scala.Double) : scala.Int = { /* compiled code */ }
 }
diff --git a/test/files/scalap/paramNames/result.test b/test/files/scalap/paramNames/result.test
index 4d3c7d0c1e..85e37f858d 100644
--- a/test/files/scalap/paramNames/result.test
+++ b/test/files/scalap/paramNames/result.test
@@ -1,4 +1,4 @@
-class ParamNames extends java.lang.Object {
+class ParamNames extends scala.AnyRef {
   def this() = { /* compiled code */ }
   def foo(s : => scala.Seq[scala.Int], s2 : => scala.Seq[scala.Any]) : scala.Unit = { /* compiled code */ }
 }
diff --git a/test/files/scalap/sequenceParam/result.test b/test/files/scalap/sequenceParam/result.test
index ed47c094fe..142d92fea3 100644
--- a/test/files/scalap/sequenceParam/result.test
+++ b/test/files/scalap/sequenceParam/result.test
@@ -1,3 +1,3 @@
-class SequenceParam extends java.lang.Object {
+class SequenceParam extends scala.AnyRef {
   def this(s : scala.Predef.String, i : scala.Int*) = { /* compiled code */ }
 }
diff --git a/test/files/scalap/simpleClass/result.test b/test/files/scalap/simpleClass/result.test
index 905046ce52..4fdf25d1cf 100644
--- a/test/files/scalap/simpleClass/result.test
+++ b/test/files/scalap/simpleClass/result.test
@@ -1,4 +1,4 @@
-class SimpleClass extends java.lang.Object {
+class SimpleClass extends scala.AnyRef {
   def this() = { /* compiled code */ }
   def foo : scala.Int = { /* compiled code */ }
 }
diff --git a/test/files/scalap/traitObject/result.test b/test/files/scalap/traitObject/result.test
index d0521043c8..104ba14f1a 100644
--- a/test/files/scalap/traitObject/result.test
+++ b/test/files/scalap/traitObject/result.test
@@ -1,8 +1,8 @@
-trait TraitObject extends java.lang.Object {
+trait TraitObject extends scala.AnyRef {
   def $init$() : scala.Unit = { /* compiled code */ }
   def foo : scala.Int = { /* compiled code */ }
 }
-object TraitObject extends java.lang.Object {
+object TraitObject extends scala.AnyRef {
   def this() = { /* compiled code */ }
   def bar : scala.Int = { /* compiled code */ }
 }
diff --git a/test/files/scalap/typeAnnotations/result.test b/test/files/scalap/typeAnnotations/result.test
index d28712f12b..407b0235c6 100644
--- a/test/files/scalap/typeAnnotations/result.test
+++ b/test/files/scalap/typeAnnotations/result.test
@@ -1,4 +1,4 @@
-abstract class TypeAnnotations[@scala.specialized R] extends java.lang.Object {
+abstract class TypeAnnotations[@scala.specialized R] extends scala.AnyRef {
   def this() = { /* compiled code */ }
   @scala.specialized
   val x : scala.Int = { /* compiled code */ }
diff --git a/test/files/scalap/valAndVar/result.test b/test/files/scalap/valAndVar/result.test
index 90081acade..e940da9801 100644
--- a/test/files/scalap/valAndVar/result.test
+++ b/test/files/scalap/valAndVar/result.test
@@ -1,4 +1,4 @@
-class ValAndVar extends java.lang.Object {
+class ValAndVar extends scala.AnyRef {
   def this() = { /* compiled code */ }
   val foo : java.lang.String = { /* compiled code */ }
   var bar : scala.Int = { /* compiled code */ }
diff --git a/test/files/scalap/wildcardType/result.test b/test/files/scalap/wildcardType/result.test
index 28147b6605..e43261db32 100644
--- a/test/files/scalap/wildcardType/result.test
+++ b/test/files/scalap/wildcardType/result.test
@@ -1,3 +1,3 @@
-class WildcardType extends java.lang.Object {
+class WildcardType extends scala.AnyRef {
   def this(f : scala.Function1[scala.Int, _]) = { /* compiled code */ }
 }