Fixes for cases where unexpected declaration descriptor hierarchy caused invalid scoping structure in js backend.

Minor refactorings.

js/js.translator/testFiles/expression/misc/cases/extensionLiteralCreatedAtNamespaceLevel.kt

@@ -0,0 +1,19 @@
+package foo
+
+class A() {
+  fun foo() = 1
+  fun a(f : A.()->Int) : Int {
+      return f()
+  }
+}
+
+var d = 0
+
+val p : A.()->Int = {
+  d = foo()
+  d++
+}
+
+val c = A().a(p)
+
+fun box() = (c == 1)

js/js.translator/testFiles/expression/misc/cases/funInConstructorBlock.kt

@@ -0,0 +1,19 @@
+package foo
+
+class A() {
+
+  fun lold() = true
+  val p : ()->Boolean
+  {
+      $p = {{lold()}()}
+  }
+}
+
+
+fun box() : Boolean {
+  return A().p()
+}
+
+fun main(arg : Array<String>) {
+    println(box())
+}

js/js.translator/testFiles/expression/misc/cases/namespacePropertyCalledAsFun.kt

@@ -0,0 +1,7 @@
+package foo
+
+fun lold() = true
+
+val p = {{lold()}()}
+
+fun box() = p() && foo.p()

js/js.translator/testFiles/expression/misc/cases/temporaryVariableCreatedInNamespaceInitializer.kt

@@ -0,0 +1,6 @@
+package foo
+
+var p = 0
+val c = p++ // creates temporary value
+
+fun box() = (p == 1) && (c == 0)