Misc: Use TODO() consistently in implementation stubs

#KT-13589 Fixed

idea/testData/quickfix/implement/abstract.kt.after

@@ -10,7 +10,7 @@ private abstract class Base {
 
 private class BaseImpl : Base() {
     override var x: Int
-        get() = throw UnsupportedOperationException()
+        get() = TODO("not implemented") //To change initializer of created properties use File | Settings | File Templates.
         set(value) {
         }
 

idea/testData/quickfix/implement/nested.kt.after

@@ -17,7 +17,7 @@ class Container {
 
 class BaseImpl : Container.Base {
     override val x: Boolean
-        get() = throw UnsupportedOperationException()
+        get() = TODO("not implemented") //To change initializer of created properties use File | Settings | File Templates.
 
     override fun bar(z: Int): String {
         TODO("not implemented") //To change body of created functions use File | Settings | File Templates.

idea/testData/quickfix/implement/nestedPrivateInterface.kt.after

@@ -9,7 +9,7 @@ class Container {
 
     class BaseImpl : Base {
         override var z: Double
-            get() = throw UnsupportedOperationException()
+            get() = TODO("not implemented") //To change initializer of created properties use File | Settings | File Templates.
             set(value) {
             }
     }