KT-2724 No completion in class initializers

#KT-2724 Fixed

idea/testData/completion/basic/InClassInitializer.kt

@@ -0,0 +1,12 @@
+val testExternal
+
+class Some(testParam : Int) {
+  private val myVal : Int
+
+  {
+    val testing = 12
+    myVal = test<caret>
+  }
+}
+
+// EXIST: testParam, testExternal, testing

idea/testData/completion/basic/InFunInClassInitializer.kt

@@ -0,0 +1,11 @@
+val some = 12
+class Some(someParam : Int) {
+  {
+    fun internalFun(someInternal : Int) : Int {
+      return some<caret>
+    }
+  }
+}
+
+// EXIST: some, someInternal, someParam
+