Fixes SI-5629.

Adds an additional argument to the unify method in
specialization - `tparams`. When this parameter is set
to `true`, unification is done over type parameters in
poly types as well.

Additionally, the unification in specialization now
works over type bounds.

This ensures that in the below example:

trait Foo[@specialized(Int) A] {
  def bar[B <: A](b: B) {}
}

class IntFoo extends Foo[Int] {
  override def bar[B <: Int](b: B) {}
}

the method `bar` gets correctly determined
as a method that needs a special override
for its `bar$mcI$sp`.

1 files changed, 2 insertions, 0 deletions

diff --git a/test/files/run/t5629.check b/test/files/run/t5629.check
new file mode 100644
index 0000000000..6a2d630f4e
--- /dev/null
+++ b/test/files/run/t5629.check
@@ -0,0 +1,2 @@
+int child got: 33
+any child got: 33