Dropped redundant code which was required for lambda signature completion when the syntax was different

#KT-12033 Fixed

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/KotlinCompletionContributor.kt

@@ -180,19 +180,12 @@ class KotlinCompletionContributor : CompletionContributor() {
 
         val lambda = leaf?.parents?.firstOrNull { it is KtFunctionLiteral } ?: return null
 
-        val lambdaChild = leaf!!.parents.takeWhile { it != lambda }.lastOrNull() ?: return null
-        if (lambdaChild is KtParameterList) return CompletionUtilCore.DUMMY_IDENTIFIER_TRIMMED
+        val lambdaChild = leaf!!.parents.takeWhile { it != lambda }.lastOrNull()
 
-        if (lambdaChild !is KtBlockExpression) return null
-        val blockChild = leaf.parents.takeWhile { it != lambdaChild }.lastOrNull()
-        if (blockChild !is PsiErrorElement) return null
-        val inIncompleteSignature = blockChild.siblings(forward = false, withItself = false).all {
-            when (it) {
-                is PsiWhiteSpace, is PsiComment -> true
-                else -> false
-            }
-        }
-        return if (inIncompleteSignature) CompletionUtilCore.DUMMY_IDENTIFIER_TRIMMED + "->" else null
+        return if (lambdaChild is KtParameterList)
+            CompletionUtilCore.DUMMY_IDENTIFIER_TRIMMED
+        else
+            null
 
     }
 

idea/idea-completion/testData/basic/common/KT12033.kt

@@ -0,0 +1,8 @@
+fun main(foo: Foo) {
+    foo.apply {
+        is<caret>
+    }
+}
+class Foo(val isValid: String)
+
+// EXIST: isValid

idea/idea-completion/tests/org/jetbrains/kotlin/idea/completion/test/JSBasicCompletionTestGenerated.java

@@ -469,6 +469,12 @@ public class JSBasicCompletionTestGenerated extends AbstractJSBasicCompletionTes
             doTest(fileName);
         }
 
+        @TestMetadata("KT12033.kt")
+        public void testKT12033() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/basic/common/KT12033.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("LocalMultideclarationValues.kt")
         public void testLocalMultideclarationValues() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/basic/common/LocalMultideclarationValues.kt");

idea/idea-completion/tests/org/jetbrains/kotlin/idea/completion/test/JvmBasicCompletionTestGenerated.java

@@ -469,6 +469,12 @@ public class JvmBasicCompletionTestGenerated extends AbstractJvmBasicCompletionT
             doTest(fileName);
         }
 
+        @TestMetadata("KT12033.kt")
+        public void testKT12033() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/basic/common/KT12033.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("LocalMultideclarationValues.kt")
         public void testLocalMultideclarationValues() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/basic/common/LocalMultideclarationValues.kt");