KT-21928 Structure view doesn't show default constructor

idea/idea-analysis/src/org/jetbrains/kotlin/idea/structureView/KotlinStructureViewElement.kt

@@ -126,5 +126,8 @@ private class AssignableLazyProperty<in R, T : Any>(val init: () -> T) : ReadWri
     }
 }
 
-fun KtClassOrObject.getStructureDeclarations() = primaryConstructorParameters.filter { it.hasValOrVar() } + declarations
+fun KtClassOrObject.getStructureDeclarations() =
+        (primaryConstructor?.let { listOf(it) } ?: emptyList()) +
+        primaryConstructorParameters.filter { it.hasValOrVar() } +
+        declarations
 

idea/testData/structureView/fileStructure/InheritedJavaMembers.after

@@ -1,6 +1,7 @@
 -InheritedJavaMembers.kt
  -InheritedJavaMembers
   call(): String! location=→Callable
+  constructor InheritedJavaMembers()
   equals(Any?): Boolean location=→Any
   hashCode(): Int location=→Any
   test(): Unit

idea/testData/structureView/fileStructure/InheritedSynthesizedFromDataClass.after

@@ -3,4 +3,5 @@
   a: Int location=→TestData
   field: Int
   some(): Unit location=→TestData
- TestData
+ -TestData
+  constructor TestData(Int)

idea/testData/structureView/fileStructure/Render.after

@@ -3,10 +3,13 @@
  -A2
   a: Int
   b: [ERROR : Annotation is absent]
+  constructor A2(Int, [ERROR : Type annotation was missing for parameter b] = ...)
  -A3
   a: Int
   b: String
+  constructor A3(Int)
  -A4
+  constructor A4(T?)
   t: T?
  -A5
   Inner1
@@ -39,3 +42,4 @@
  withDefaulArgs(Int = ..., String = ...): Unit
  -WithDefaultArgs
   a: Int
+  constructor WithDefaultArgs(Int = ..., String = ...)

idea/testData/structureView/fileStructure/Simple.after

@@ -1,5 +1,6 @@
 -Simple.kt
  -Test
+  constructor Test(String)
   foo(): Int
   other(): Unit
   some: Int