Simplify function hierarchy in reflection

Get rid of all classes except kotlin.reflect.KFunction, which will be used to
represent all kinds of simple functions.

Lots of changes to test data are related to the fact that KFunction is not an
extension function (as opposed to KMemberFunction and KExtensionFunction who
were) and so a member or an extension function reference now requires all
arguments be passed to it in the parentheses, including receivers. This is
probably temporary until we support calling any function both as a free
function and as an extension. In JS, functions and extension functions are not
interchangeable, so tests on this behavior are removed until this is supported

compiler/testData/codegen/boxWithStdlib/callableReference/function/abstractClassMember.kt

@@ -6,4 +6,4 @@ class B : A() {
     override fun foo() = "OK"
 }
 
-fun box(): String = B().(A::foo)()
+fun box(): String = (A::foo)(B())

compiler/testData/codegen/boxWithStdlib/callableReference/function/booleanNotIntrinsic.kt

@@ -1,5 +1,5 @@
 fun box(): String {
-    if (true.(Boolean::not)() != false) return "Fail 1"
-    if (false.(Boolean::not)() != true) return "Fail 2"
+    if ((Boolean::not)(true) != false) return "Fail 1"
+    if ((Boolean::not)(false) != true) return "Fail 2"
     return "OK"
 }

compiler/testData/codegen/boxWithStdlib/callableReference/function/classMemberFromClass.kt

@@ -1,7 +1,7 @@
 class A {
     fun foo(k: Int) = k
 
-    fun result() = this.(::foo)(111)
+    fun result() = (::foo)(this, 111)
 }
 
 fun box(): String {

compiler/testData/codegen/boxWithStdlib/callableReference/function/classMemberFromExtension.kt

@@ -3,7 +3,7 @@ class A {
     fun k(k: Int) = k
 }
 
-fun A.foo() = this.(::o)() + this.(A::k)(222)
+fun A.foo() = (::o)(this) + (A::k)(this, 222)
 
 fun box(): String {
     val result = A().foo()

compiler/testData/codegen/boxWithStdlib/callableReference/function/classMemberFromTopLevelStringNoArgs.kt

@@ -4,5 +4,5 @@ class A {
 
 fun box(): String {
     val x = A::foo
-    return A().x()
+    return x(A())
 }

compiler/testData/codegen/boxWithStdlib/callableReference/function/classMemberFromTopLevelStringOneStringArg.kt

@@ -4,5 +4,5 @@ class A {
 
 fun box(): String {
     val x = A::foo
-    return A().x("OK")
+    return x(A(), "OK")
 }

compiler/testData/codegen/boxWithStdlib/callableReference/function/classMemberFromTopLevelUnitNoArgs.kt

@@ -9,6 +9,6 @@ class A {
 fun box(): String {
     val a = A()
     val x = A::foo
-    a.x()
+    x(a)
     return a.result
 }

compiler/testData/codegen/boxWithStdlib/callableReference/function/classMemberFromTopLevelUnitOneStringArg.kt

@@ -9,6 +9,6 @@ class A {
 fun box(): String {
     val a = A()
     val x = A::foo
-    a.x("OK")
+    x(a, "OK")
     return a.result
 }

compiler/testData/codegen/boxWithStdlib/callableReference/function/enumNameMethod.kt

@@ -3,7 +3,7 @@ enum class E {
 }
 
 fun box(): String {
-    val i = E.I.(E::name)()
+    val i = (E::name)(E.I)
     if (i != "I") return "Fail $i"
     return "OK"
 }

compiler/testData/codegen/boxWithStdlib/callableReference/function/equalsIntrinsic.kt

@@ -1,3 +1,3 @@
 class A
 
-fun box() = if (A().(A::equals)(A())) "Fail" else "OK"
+fun box() = if ((A::equals)(A(), A())) "Fail" else "OK"

compiler/testData/codegen/boxWithStdlib/callableReference/function/extensionFromClass.kt

@@ -1,5 +1,5 @@
 class A {
-    fun result() = this.(::foo)("OK")
+    fun result() = (::foo)(this, "OK")
 }
 
 fun A.foo(x: String) = x

compiler/testData/codegen/boxWithStdlib/callableReference/function/extensionFromExtension.kt

@@ -1,6 +1,6 @@
 class A
 
-fun A.foo() = this.(A::bar)("OK")
+fun A.foo() = (A::bar)(this, "OK")
 
 fun A.bar(x: String) = x
 

compiler/testData/codegen/boxWithStdlib/callableReference/function/extensionFromTopLevelStringNoArgs.kt

@@ -4,5 +4,5 @@ fun A.foo() = "OK"
 
 fun box(): String {
     val x = A::foo
-    return A().x()
+    return x(A())
 }

compiler/testData/codegen/boxWithStdlib/callableReference/function/extensionFromTopLevelStringOneStringArg.kt

@@ -4,5 +4,5 @@ fun A.foo(result: String) = result
 
 fun box(): String {
     val x = A::foo
-    return A().x("OK")
+    return x(A(), "OK")
 }

compiler/testData/codegen/boxWithStdlib/callableReference/function/extensionFromTopLevelUnitNoArgs.kt

@@ -9,6 +9,6 @@ fun A.foo() {
 fun box(): String {
     val a = A()
     val x = A::foo
-    a.x()
+    x(a)
     return a.result
 }

compiler/testData/codegen/boxWithStdlib/callableReference/function/extensionFromTopLevelUnitOneStringArg.kt

@@ -9,6 +9,6 @@ fun A.foo(newResult: String) {
 fun box(): String {
     val a = A()
     val x = A::foo
-    a.x("OK")
+    x(a, "OK")
     return a.result
 }

compiler/testData/codegen/boxWithStdlib/callableReference/function/genericMember.kt

@@ -2,4 +2,4 @@ class A<T>(val t: T) {
     fun foo(): T = t
 }
 
-fun box() = A("OK").(A<String>::foo)()
+fun box() = (A<String>::foo)(A("OK"))

compiler/testData/codegen/boxWithStdlib/callableReference/function/innerConstructorFromClass.kt

@@ -4,7 +4,7 @@ class A {
         val k = 222
     }
     
-    fun result() = this.(A::Inner)().o + this.(::Inner)().k
+    fun result() = (A::Inner)(this).o + (::Inner)(this).k
 }
 
 fun box(): String {

compiler/testData/codegen/boxWithStdlib/callableReference/function/innerConstructorFromExtension.kt

@@ -5,7 +5,7 @@ class A {
     }
 }
 
-fun A.foo() = this.(A::Inner)().o + this.(::Inner)().k
+fun A.foo() = (A::Inner)(this).o + (::Inner)(this).k
 
 fun box(): String {
     val result = A().foo()

compiler/testData/codegen/boxWithStdlib/callableReference/function/innerConstructorFromTopLevelNoArgs.kt

@@ -6,7 +6,7 @@ class A {
 }
 
 fun box(): String {
-    val result = (::A)().(A::Inner)().o + A().(A::Inner)().k
+    val result = (A::Inner)((::A)()).o + (A::Inner)(A()).k
     if (result != 333) return "Fail $result"
     return "OK"
 }

compiler/testData/codegen/boxWithStdlib/callableReference/function/innerConstructorFromTopLevelOneStringArg.kt

@@ -3,7 +3,7 @@ class A {
 }
 
 fun box(): String {
-    val result = (::A)().(A::Inner)(111).result + A().(A::Inner)(222).result
+    val result = (A::Inner)((::A)(), 111).result + (A::Inner)(A(), 222).result
     if (result != 333) return "Fail $result"
     return "OK"
 }

compiler/testData/codegen/boxWithStdlib/callableReference/function/local/captureOuter.kt

@@ -8,5 +8,5 @@ class Outer {
 
 fun box(): String {
     val f = Outer.Inner::foo
-    return Outer().Inner().f()
+    return f(Outer().Inner())
 }

compiler/testData/codegen/boxWithStdlib/callableReference/function/local/classMember.kt

@@ -4,5 +4,5 @@ fun box(): String {
     }
 
     val ref = Local::foo
-    return Local().ref()
+    return ref(Local())
 }

compiler/testData/codegen/boxWithStdlib/callableReference/function/local/enumExtendsTrait.kt

@@ -7,5 +7,5 @@ enum class E : Named {
 }
 
 fun box(): String {
-    return E.OK.(Named::name)()
+    return (Named::name)(E.OK)
 }

compiler/testData/codegen/boxWithStdlib/callableReference/function/local/extension.kt

@@ -2,5 +2,5 @@ class A
 
 fun box(): String {
     fun A.foo() = "OK"
-    return A().(A::foo)()
+    return (A::foo)(A())
 }

compiler/testData/codegen/boxWithStdlib/callableReference/function/local/extensionToLocalClass.kt

@@ -1,5 +1,5 @@
 fun box(): String {
     class A
     fun A.foo() = "OK"
-    return (::A)().(A::foo)()
+    return (A::foo)((::A)())
 }

compiler/testData/codegen/boxWithStdlib/callableReference/function/local/extensionToPrimitive.kt

@@ -1,4 +1,4 @@
 fun box(): String {
     fun Int.is42With(that: Int) = this + 2 * that == 42
-    return if (16.(Int::is42With)(13)) "OK" else "Fail"
+    return if ((Int::is42With)(16, 13)) "OK" else "Fail"
 }

compiler/testData/codegen/boxWithStdlib/callableReference/function/local/extensionWithClosure.kt

@@ -6,6 +6,6 @@ fun box(): String {
     fun A.ext() { result = "OK" }
 
     val f = A::ext
-    A().f()
+    f(A())
     return result
 }

compiler/testData/codegen/boxWithStdlib/callableReference/function/local/genericMember.kt

@@ -4,5 +4,5 @@ fun box(): String {
     }
 
     val ref = Id<String>::invoke
-    return Id<String>().ref("OK")
+    return ref(Id<String>(), "OK")
 }

compiler/testData/codegen/boxWithStdlib/callableReference/function/local/localClassMember.kt

@@ -7,5 +7,5 @@ fun box(): String {
 
     val member = Local::foo
     val instance = Local()
-    return instance.member()
+    return member(instance)
 }

compiler/testData/codegen/boxWithStdlib/callableReference/function/objectMemberUnitNoArgs.kt

@@ -8,6 +8,6 @@ object A {
 
 fun box(): String {
     val x = A::foo
-    A.x()
+    x(A)
     return A.result
 }

compiler/testData/codegen/boxWithStdlib/callableReference/function/objectMemberUnitOneStringArg.kt

@@ -8,6 +8,6 @@ object A {
 
 fun box(): String {
     val x = A::foo
-    A.x("OK")
+    x(A, "OK")
     return A.result
 }

compiler/testData/codegen/boxWithStdlib/callableReference/function/privateClassMember.kt

@@ -1,7 +1,7 @@
 class A {
     private fun foo() = "OK"
 
-    fun bar() = this.(::foo)()
+    fun bar() = (::foo)(this)
 }
 
 fun box() = A().bar()

compiler/testData/codegen/boxWithStdlib/callableReference/function/traitImplMethodWithClassReceiver.kt

@@ -4,7 +4,7 @@ interface T {
 
 class B : T {
     inner class C {
-        fun bar() = this@B.(::foo)()
+        fun bar() = (::foo)(this@B)
     }
 }
 

compiler/testData/codegen/boxWithStdlib/callableReference/function/traitMember.kt

@@ -6,4 +6,4 @@ class B : A {
     override fun foo() = "OK"
 }
 
-fun box() = B().(A::foo)()
+fun box() = (A::foo)(B())