Rewritten NameValidatorImpl to be both more efficient and more correct

idea/testData/refactoring/introduceParameter/substituteExplicitThisInMember.kt.after

@@ -8,12 +8,12 @@ class A(val a: Int) {
 }
 
 fun test() {
-    val a = A(1)
-    val a1 = A(2)
-    a.foo(a.a + a1.a)
+    val a2 = A(1)
+    val a3 = A(2)
+    a2.foo(a2.a + a3.a)
     with(A(1)) {
         val a1 = A(2)
-        foo(this.a + a1.a)
+        foo(a + a1.a)
         val a = A(2)
         this.foo(this.a + a.a)
     }

idea/testData/refactoring/introduceParameter/substituteImplicitThisInMember.kt.after

@@ -8,12 +8,12 @@ class A(val a: Int) {
 }
 
 fun test() {
-    val a = A(1)
-    val a1 = A(2)
-    a.foo(a.a + a1.a)
+    val a2 = A(1)
+    val a3 = A(2)
+    a2.foo(a2.a + a3.a)
     with(A(1)) {
         val a1 = A(2)
-        foo(this.a + a1.a)
+        foo(a + a1.a)
         val a = A(2)
         this.foo(this.a + a.a)
     }

idea/testData/refactoring/introduceVariable/NameSuggestionBug2.kt

@@ -0,0 +1,12 @@
+class For {
+    var xxx: For? = null
+}
+
+
+fun foo(f: For) {
+    <selection>f.xxx</selection>
+
+    if (true) {
+        val xxx = 1
+    }
+}

idea/testData/refactoring/introduceVariable/NameSuggestionBug2.kt.after

@@ -0,0 +1,12 @@
+class For {
+    var xxx: For? = null
+}
+
+
+fun foo(f: For) {
+    val xxx1 = f.xxx
+
+    if (true) {
+        val xxx = 1
+    }
+}